Bump protocol version

BUGS.rst

@@ -4,18 +4,6 @@ or promised features of NEO (marked with N).
 
 All the listed bugs will be fixed with high priority.
 
-(Z) Conflict resolution not fully implemented
----------------------------------------------
-
-Even with a single storage node, so-called 'deadlock avoidance' may
-happen to in order to resolve conflicts. In such cases, conflicts will not be
-resolved even if your _p_resolveConflict() method would succeed, leading to a
-normal ConflictError.
-
-Although this should happen rarely enough not to affect performance, this can
-be an issue if your application can't afford restarting the transaction,
-e.g. because it interacted with external environment.
-
 (N) Storage failure or update may lead to POSException or break undoLog()
 -------------------------------------------------------------------------
 

TODO

@@ -15,16 +15,13 @@
 
     General
     - Review XXX/TODO code tags (CODE)
-    - Coverage for functional tests (i.e. collect results from subprocesses)
     - When all cells are OUT_OF_DATE in backup mode, the one with most data
       could become UP_TO_DATE with appropriate backup_tid, so that the cluster
       stays operational. (FEATURE)
     - Finish renaming UUID into NID everywhere (CODE)
-    - Implements delayed connection acceptation.
+    - Delayed connection acceptation even when a storage node is not ready ?
       Currently, any node that connects too early to another that is busy for
-      some reasons is immediately rejected with the 'not ready' error code. This
-      should be replaced by a queue in the listening node that keep a pool a
-      nodes that will be accepted late, when the conditions will be satisfied.
+      some reasons is immediately rejected with the 'not ready' error code.
       This is mainly the case for :
         - Client rejected before the cluster is operational
         - Empty storages rejected during recovery process
@@ -41,18 +38,11 @@
     - Clarify handler methods to call when a connection is accepted from a
       listening conenction and when remote node is identified
       (cf. neo/lib/bootstrap.py).
-    - Choose how to handle a storage integrity verification when it comes back.
-      Do the replication process, the verification stage, with or without
-      unfinished transactions, cells have to set as outdated, if yes, should the
-      partition table changes be broadcasted ? (BANDWITH, SPEED)
-    - Make SIGINT on primary master change cluster in STOPPING state.
     - Review PENDING/HIDDEN/SHUTDOWN states, don't use notifyNodeInformation()
       to do a state-switch, use a exception-based mechanism ? (CODE)
     - Review handler split (CODE)
       The current handler split is the result of small incremental changes. A
       global review is required to make them square.
-    - Review node notifications. Eg. A storage don't have to be notified of new
-      clients but only when one is lost.
     - Review transactional isolation of various methods
       Some methods might not implement proper transaction isolation when they
       should. An example is object history (undoLog), which can see data
@@ -63,14 +53,12 @@
       partitions. Currently, reads succeed because feeding nodes don't delete
       anything while the cluster is operational, for performance reasons:
       deletion of dropped partitions must be reimplemented in a scalable way.
-      (HIGH AVAILABILITY)
+      The same thing happens for writes: storage nodes must discard
+      stores/checks of dropped partitions (in lockObject, that can be done by
+      raising ConflictError(None)). (HIGH AVAILABILITY)
 
     Storage
     - Use libmysqld instead of a stand-alone MySQL server.
-    - Notify master when storage becomes available for clients (LATENCY)
-      Currently, storage presence is broadcasted to client nodes too early, as
-      the storage node would refuse them until it has only up-to-date data (not
-      only up-to-date cells, but also a partition table and node states).
     - In backup mode, 2 simultaneous replication should be possible so that:
       - outdated cells does not block backup for too long time
       - constantly modified partitions does not prevent outdated cells to
@@ -78,9 +66,7 @@
       Current behaviour is undefined and the above 2 scenarios may happen.
     - Create a specialized PartitionTable that know the database and replicator
       to remove duplicates and remove logic from handlers (CODE)
-    - Consider insert multiple objects at time in the database, with taking care
-      of maximum SQL request size allowed. (SPEED)
-    - Make listening address and port optionnal, and if they are not provided
+    - Make listening address and port optional, and if they are not provided
       listen on all interfaces on any available port.
     - Make replication speed configurable (HIGH AVAILABILITY)
       In its current implementation, replication runs at lowest priority, to
@@ -125,15 +111,13 @@
       instead of parsing the whole partition table. (SPEED)
 
     Client
+    - Race conditions on the partition table ?
+      (update by the poll thread vs. access by other threads)
     - Merge Application into Storage (SPEED)
     - Optimize cache.py by rewriting it either in C or Cython (LOAD LATENCY)
     - Use generic bootstrap module (CODE)
     - If too many storage nodes are dead, the client should check the partition
       table hasn't changed by pinging the master and retry if necessary.
-    - Implement IStorageRestoreable (ZODB API) in order to preserve data
-      serials (i.e. undo information).
-    - Fix and reenable deadlock avoidance (SPEED). This is required for
-      neo.threaded.test.Test.testDeadlockAvoidance
 
     Admin
     - Make admin node able to monitor multiple clusters simultaneously
@@ -141,6 +125,7 @@
     - Add ctl command to list last transactions, like fstail for FileStorage.
 
     Tests
+    - Split neo/tests/threaded/test.py
     - Use another mock library: Python 3.3+ has unittest.mock, which is
       available for earlier versions at https://pypi.python.org/pypi/mock
 

neo/client/Storage.py

@@ -89,16 +89,16 @@ class Storage(BaseStorage.BaseStorage,
         """
         Note: never blocks in NEO.
         """
-        return self.app.tpc_begin(transaction, tid, status)
+        return self.app.tpc_begin(self, transaction, tid, status)
 
     def tpc_vote(self, transaction):
-        return self.app.tpc_vote(transaction, self.tryToResolveConflict)
+        return self.app.tpc_vote(transaction)
 
     def tpc_abort(self, transaction):
         return self.app.tpc_abort(transaction)
 
     def tpc_finish(self, transaction, f=None):
-        return self.app.tpc_finish(transaction, self.tryToResolveConflict, f)
+        return self.app.tpc_finish(transaction, f)
 
     def store(self, oid, serial, data, version, transaction):
         assert version == '', 'Versions are not supported'
@@ -128,7 +128,7 @@ class Storage(BaseStorage.BaseStorage,
 
     # undo
     def undo(self, transaction_id, txn):
-        return self.app.undo(transaction_id, txn, self.tryToResolveConflict)
+        return self.app.undo(transaction_id, txn)
 
     def undoLog(self, first=0, last=-20, filter=None):
         return self.app.undoLog(first, last, filter)
@@ -167,8 +167,7 @@ class Storage(BaseStorage.BaseStorage,
 
     def importFrom(self, source, start=None, stop=None, preindex=None):
         """ Allow import only a part of the source storage """
-        return self.app.importFrom(source, start, stop,
-                self.tryToResolveConflict, preindex)
+        return self.app.importFrom(self, source, start, stop, preindex)
 
     def pack(self, t, referencesf, gc=False):
         if gc:

neo/client/handlers/master.py

@@ -147,7 +147,7 @@ class PrimaryNotificationsHandler(MTEventHandler):
             logging.critical(msg)
             app.master_conn = None
             for txn_context in app.txn_contexts():
-                txn_context['error'] = msg
+                txn_context.error = msg
         try:
             del app.pt
         except AttributeError:
@@ -182,9 +182,9 @@ class PrimaryNotificationsHandler(MTEventHandler):
         if self.app.pt.filled():
             self.app.pt.update(ptid, cell_list, self.app.nm)
 
-    def notifyNodeInformation(self, conn, node_list):
+    def notifyNodeInformation(self, conn, timestamp, node_list):
         super(PrimaryNotificationsHandler, self).notifyNodeInformation(
-            conn, node_list)
+            conn, timestamp, node_list)
         # XXX: 'update' automatically closes DOWN nodes. Do we really want
         #      to do the same thing for nodes in other non-running states ?
         getByUUID = self.app.nm.getByUUID
@@ -194,6 +194,13 @@ class PrimaryNotificationsHandler(MTEventHandler):
                 if node and node.isConnected():
                     node.getConnection().close()
 
+    def notifyDeadlock(self, conn, ttid, locking_tid):
+        for txn_context in self.app.txn_contexts():
+            if txn_context.ttid == ttid:
+                txn_context.conflict_dict[None] = locking_tid, None
+                txn_context.wakeup(conn)
+                break
+
 class PrimaryAnswersHandler(AnswerBaseHandler):
     """ Handle that process expected packets from the primary master """
 
@@ -204,6 +211,10 @@ class PrimaryAnswersHandler(AnswerBaseHandler):
         oid_list.reverse()
         self.app.new_oid_list = oid_list
 
+    def incompleteTransaction(self, conn, message):
+        raise NEOStorageError("storage nodes for which vote failed can not be"
+            " disconnected without making the cluster non-operational")
+
     def answerTransactionFinished(self, conn, _, tid):
         self.app.setHandlerData(tid)
 

neo/client/pool.py

@@ -28,7 +28,7 @@ from .exception import NEOPrimaryMasterLost, NEOStorageError
 # failed in the past.
 MAX_FAILURE_AGE = 600
 
-# Cell list sort keys
+# Cell list sort keys, only for read access
 #   We are connected to storage node hosting cell, high priority
 CELL_CONNECTED = -1
 #   normal priority
@@ -36,6 +36,7 @@ CELL_GOOD = 0
 #   Storage node hosting cell failed recently, low priority
 CELL_FAILED = 1
 
+
 class ConnectionPool(object):
     """This class manages a pool of connections to storage nodes."""
 
@@ -86,12 +87,12 @@ class ConnectionPool(object):
     def getConnForCell(self, cell):
         return self.getConnForNode(cell.getNode())
 
-    def iterateForObject(self, object_id, readable=False):
+    def iterateForObject(self, object_id):
         """ Iterate over nodes managing an object """
         pt = self.app.pt
         if type(object_id) is str:
             object_id = pt.getPartition(object_id)
-        cell_list = pt.getCellList(object_id, readable)
+        cell_list = pt.getCellList(object_id, True)
         if not cell_list:
             raise NEOStorageError('no storage available')
         getConnForNode = self.getConnForNode
@@ -106,7 +107,7 @@ class ConnectionPool(object):
                 node = cell.getNode()
                 conn = getConnForNode(node)
                 if conn is not None:
-                    yield node, conn
+                    yield conn
                 # Re-check if node is running, as our knowledge of its
                 # state can have changed during connection attempt.
                 elif node.isRunning():

neo/client/transactions.py

+#
+# Copyright (C) 2017  Nexedi SA
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from ZODB.POSException import StorageTransactionError
+from neo.lib.connection import ConnectionClosed
+from neo.lib.locking import SimpleQueue
+from neo.lib.protocol import Packets
+from .exception import NEOStorageError
+
+@apply
+class _WakeupPacket(object):
+
+    handler_method_name = 'pong'
+    decode = tuple
+    getId = int
+
+class Transaction(object):
+
+    cache_size = 0  # size of data in cache_dict
+    data_size = 0   # size of data in data_dict
+    error = None
+    locking_tid = None
+    voted = False
+    ttid = None     # XXX: useless, except for testBackupReadOnlyAccess
+
+    def __init__(self, txn):
+        self.queue = SimpleQueue()
+        self.txn = txn
+        # data being stored
+        self.data_dict = {}                      # {oid: (value, [node_id])}
+        # data stored: this will go to the cache on tpc_finish
+        self.cache_dict = {}                     # {oid: value}
+        # conflicts to resolve
+        self.conflict_dict = {}                  # {oid: (base_serial, serial)}
+        # resolved conflicts
+        self.resolved_dict = {}                  # {oid: serial}
+        # Keys are node ids instead of Node objects because a node may
+        # disappear from the cluster. In any case, we always have to check
+        # if the id is still known by the NodeManager.
+        # status: 0 -> check only, 1 -> store, 2 -> failed
+        self.involved_nodes = {}                 # {node_id: status}
+
+    def wakeup(self, conn):
+        self.queue.put((conn, _WakeupPacket, {}))
+
+    def write(self, app, packet, object_id, store=1, **kw):
+        uuid_list = []
+        pt = app.pt
+        involved = self.involved_nodes
+        object_id = pt.getPartition(object_id)
+        for cell in pt.getCellList(object_id):
+            node = cell.getNode()
+            uuid = node.getUUID()
+            status = involved.get(uuid, -1)
+            if status < store:
+                involved[uuid] = store
+            elif status > 1:
+                continue
+            conn = app.cp.getConnForNode(node)
+            if conn is not None:
+                try:
+                    if status < 0 and self.locking_tid and 'oid' in kw:
+                        # A deadlock happened but this node is not aware of it.
+                        # Tell it to write-lock with the same locking tid as
+                        # for the other nodes. The condition on kw is because
+                        # we don't need that for transaction metadata.
+                        conn.ask(Packets.AskRebaseTransaction(
+                            self.ttid, self.locking_tid), queue=self.queue)
+                    conn.ask(packet, queue=self.queue, **kw)
+                    uuid_list.append(uuid)
+                    continue
+                except ConnectionClosed:
+                    pass
+            involved[uuid] = 2
+        if uuid_list:
+            return uuid_list
+        raise NEOStorageError(
+            'no storage available for write to partition %s' % object_id)
+
+    def written(self, app, uuid, oid):
+        # When a node that is being disconnected by the master because it was
+        # not part of the transaction that caused a conflict, we may receive a
+        # positive answer (not to be confused with lockless stores) before the
+        # conflict. Because we have no way to identify such case, we must keep
+        # the data in self.data_dict until all nodes have answered so we remain
+        # able to resolve conflicts.
+        try:
+            data, uuid_list = self.data_dict[oid]
+            uuid_list.remove(uuid)
+        except KeyError:
+            # 1. store to S1 and S2
+            # 2. S2 reports a conflict
+            # 3. store to S1 and S2 # conflict resolution
+            # 4. S1 does not report a conflict (lockless)
+            # 5. S2 answers before S1 for the second store
+            return
+        except ValueError:
+            # The most common case for this exception is because nodeLost()
+            # tries all oids blindly. Other possible cases:
+            # - like above (KeyError), but with S2 answering last
+            # - answer to resolved conflict before the first answer from a
+            #   node that was being disconnected by the master
+            return
+        if uuid_list:
+            return
+        del self.data_dict[oid]
+        if type(data) is str:
+            size = len(data)
+            self.data_size -= size
+            size += self.cache_size
+            if size < app._cache._max_size:
+                self.cache_size = size
+            else:
+                # Do not cache data past cache max size, as it
+                # would just flush it on tpc_finish. This also
+                # prevents memory errors for big transactions.
+                data = None
+        self.cache_dict[oid] = data
+
+    def nodeLost(self, app, uuid):
+        self.involved_nodes[uuid] = 2
+        for oid in list(self.data_dict):
+            self.written(app, uuid, oid)
+
+
+class TransactionContainer(dict):
+    # IDEA: Drop this container and use the new set_data/data API on
+    #       transactions (requires transaction >= 1.6).
+
+    def pop(self, txn):
+        return dict.pop(self, id(txn), None)
+
+    def get(self, txn):
+        try:
+            return self[id(txn)]
+        except KeyError:
+            raise StorageTransactionError("unknown transaction %r" % txn)
+
+    def new(self, txn):
+        key = id(txn)
+        if key in self:
+            raise StorageTransactionError("commit of transaction %r"
+                                          " already started" % txn)
+        context = self[key] = Transaction(txn)
+        return context

neo/lib/bootstrap.py

@@ -38,6 +38,7 @@ class BootstrapManager(EventHandler):
         self.num_replicas = None
         self.num_partitions = None
         self.current = None
+        app.nm.reset()
 
     uuid = property(lambda self: self.app.uuid)
 

neo/lib/dispatcher.py

@@ -19,17 +19,15 @@ from .locking import Lock, Empty
 EMPTY = {}
 NOBODY = []
 
-class ForgottenPacket(object):
-    """
-      Instances of this class will be pushed to queue when an expected answer
-      is being forgotten. Its purpose is similar to pushing "None" when
-      connection is closed, but the meaning is different.
-    """
-    def __init__(self, msg_id):
-        self.msg_id = msg_id
+@apply
+class _ConnectionClosed(object):
 
-    def getId(self):
-        return self.msg_id
+    handler_method_name = 'connectionClosed'
+    decode = tuple
+
+    class getId(object):
+        def __eq__(self, other):
+            return True
 
 def giant_lock(func):
     def wrapped(self, *args, **kw):
@@ -88,7 +86,7 @@ class Dispatcher:
 
     def unregister(self, conn):
         """ Unregister a connection and put fake packet in queues to unlock
-        threads excepting responses from that connection """
+        threads expecting responses from that connection """
         self.lock_acquire()
         try:
             message_table = self.message_table.pop(id(conn), EMPTY)
@@ -101,25 +99,10 @@ class Dispatcher:
                 continue
             queue_id = id(queue)
             if queue_id not in notified_set:
-                queue.put((conn, None, None))
+                queue.put((conn, _ConnectionClosed, EMPTY))
                 notified_set.add(queue_id)
             _decrefQueue(queue)
 
-    @giant_lock
-    def forget(self, conn, msg_id):
-        """ Forget about a specific message for a specific connection.
-        Actually makes it "expected by nobody", so we know we can ignore it,
-        and not detect it as an error. """
-        message_table = self.message_table[id(conn)]
-        queue = message_table[msg_id]
-        if queue is NOBODY:
-            raise KeyError, 'Already expected by NOBODY: %r, %r' % (
-                conn, msg_id)
-        queue.put((conn, ForgottenPacket(msg_id), None))
-        self.queue_dict[id(queue)] -= 1
-        message_table[msg_id] = NOBODY
-        return queue
-
     @giant_lock
     def forget_queue(self, queue, flush_queue=True):
         """
@@ -137,9 +120,7 @@ class Dispatcher:
                     found += 1
                     message_table[msg_id] = NOBODY
         refcount = self.queue_dict.pop(id(queue), 0)
-        if refcount != found:
-            raise ValueError('We hit a refcount bug: %s queue uses ' \
-                'expected, %s found' % (refcount, found))
+        assert refcount == found, (refcount, found)
         if flush_queue:
             get = queue.get
             while True:

neo/lib/handler.py

@@ -15,7 +15,9 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import sys
+from collections import deque
 from . import logging
+from .connection import ConnectionClosed
 from .protocol import (
     NodeStates, Packets, Errors, BackendNotImplemented,
     BrokenNodeDisallowedError, NotReadyError, PacketMalformedError,
@@ -23,6 +25,10 @@ from .protocol import (
 from .util import cached_property
 
 
+class DelayEvent(Exception):
+    pass
+
+
 class EventHandler(object):
     """This class handles events."""
 
@@ -64,6 +70,9 @@ class EventHandler(object):
                 raise UnexpectedPacketError('no handler found')
             args = packet.decode() or ()
             method(conn, *args, **kw)
+        except DelayEvent:
+            assert not kw, kw
+            self.getEventQueue().queueEvent(method, conn, args)
         except UnexpectedPacketError, e:
             if not conn.isClosed():
                 self.__unexpectedPacket(conn, packet, *e.args)
@@ -165,9 +174,9 @@ class EventHandler(object):
             return
         conn.close()
 
-    def notifyNodeInformation(self, conn, node_list):
+    def notifyNodeInformation(self, conn, *args):
         app = self.app
-        app.nm.update(app, node_list)
+        app.nm.update(app, *args)
 
     def ping(self, conn):
         conn.answer(Packets.Pong())
@@ -207,9 +216,6 @@ class EventHandler(object):
     def brokenNodeDisallowedError(self, conn, message):
         raise RuntimeError, 'broken node disallowed error: %s' % (message,)
 
-    def alreadyPendingError(self, conn, message):
-        logging.error('already pending error: %s', message)
-
     def ack(self, conn, message):
         logging.debug("no error message: %s", message)
 
@@ -264,3 +270,80 @@ class AnswerBaseHandler(EventHandler):
 
     def acceptIdentification(*args):
         pass
+
+    def connectionClosed(self, conn):
+        raise ConnectionClosed
+
+
+class _DelayedConnectionEvent(EventHandler):
+
+    handler_method_name = '_func'
+    __new__ = object.__new__
+
+    def __init__(self, func, conn, args):
+        self._args = args
+        self._conn = conn
+        self._func = func
+        self._msg_id = conn.getPeerId()
+
+    def __call__(self):
+        conn = self._conn
+        if not conn.isClosed():
+            msg_id = conn.getPeerId()
+            try:
+                self.dispatch(conn, self)
+            finally:
+                conn.setPeerId(msg_id)
+
+    def __repr__(self):
+        return '<%s: 0x%x %s>' % (self._func.__name__, self._msg_id, self._conn)
+
+    def decode(self):
+        return self._args
+
+    def getEventQueue(self):
+        raise
+
+    def getId(self):
+        return self._msg_id
+
+
+class EventQueue(object):
+
+    def __init__(self):
+        self._event_queue = deque()
+        self._executing_event = -1
+
+    def queueEvent(self, func, conn=None, args=()):
+        self._event_queue.append(func if conn is None else
+            _DelayedConnectionEvent(func, conn, args))
+
+    def executeQueuedEvents(self):
+        # Not reentrant. When processing a queued event, calling this method
+        # only tells the caller to retry all events from the beginning, because
+        # events for the same connection must be processed in chronological
+        # order.
+        self._executing_event += 1
+        if self._executing_event:
+            return
+        queue = self._event_queue
+        n = len(queue)
+        while n:
+            try:
+                queue[0]()
+            except DelayEvent:
+                queue.rotate(-1)
+            else:
+                del queue[0]
+            n -= 1
+            if self._executing_event:
+                self._executing_event = 0
+                queue.rotate(-n)
+                n = len(queue)
+        self._executing_event = -1
+
+    def logQueuedEvents(self):
+        if self._event_queue:
+            logging.info(" Pending events:")
+            for event in self._event_queue:
+                logging.info('  %r', event)

neo/lib/node.py

@@ -19,8 +19,9 @@ from os.path import exists, getsize
 import json
 
 from . import attributeTracker, logging
+from .handler import DelayEvent, EventQueue
 from .protocol import formatNodeList, uuid_str, \
-    NodeTypes, NodeStates, ProtocolError
+    NodeTypes, NodeStates, NotReadyError, ProtocolError
 
 
 class Node(object):
@@ -232,7 +233,7 @@ class MasterDB(object):
     def __iter__(self):
         return iter(self._set)
 
-class NodeManager(object):
+class NodeManager(EventQueue):
     """This class manages node status."""
     _master_db = None
 
@@ -255,9 +256,14 @@ class NodeManager(object):
             self._master_db = db = MasterDB(master_db)
             for addr in db:
                 self.createMaster(address=addr)
+        self.reset()
 
     close = __init__
 
+    def reset(self):
+        EventQueue.__init__(self)
+        self._timestamp = 0
+
     def add(self, node):
         if node in self._node_set:
             logging.warning('adding a known node %r, ignoring', node)
@@ -350,9 +356,22 @@ class NodeManager(object):
         return self._address_dict.get(address, None)
 
     def getByUUID(self, uuid, *id_timestamp):
-        """ Return the node that match with a given UUID """
+        """Return the node that matches with a given UUID
+
+        If an id timestamp is passed, DelayEvent is raised if identification
+        must be delayed. This is because we rely only on the notifications from
+        the master to recognize nodes (otherwise, we could get id conflicts)
+        and such notifications may be late in some cases, even when the master
+        expects us to not reject the connection.
+        """
         node = self._uuid_dict.get(uuid)
-        if not id_timestamp or node and (node.id_timestamp,) == id_timestamp:
+        if id_timestamp:
+            id_timestamp, = id_timestamp
+            if not node or node.id_timestamp != id_timestamp:
+                if self._timestamp < id_timestamp:
+                    raise DelayEvent
+                # The peer got disconnected from the master.
+                raise NotReadyError('unknown by master')
         return node
 
     def _createNode(self, klass, address=None, uuid=None, **kw):
@@ -389,7 +408,9 @@ class NodeManager(object):
     def createFromNodeType(self, node_type, **kw):
         return self._createNode(NODE_TYPE_MAPPING[node_type], **kw)
 
-    def update(self, app, node_list):
+    def update(self, app, timestamp, node_list):
+        assert self._timestamp < timestamp, (self._timestamp, timestamp)
+        self._timestamp = timestamp
         node_set = self._node_set.copy() if app.id_timestamp is None else None
         for node_type, addr, uuid, state, id_timestamp in node_list:
             # This should be done here (although klass might not be used in this
@@ -443,12 +464,14 @@ class NodeManager(object):
             for node in node_set - self._node_set:
                 self.remove(node)
         self.log()
+        self.executeQueuedEvents()
 
     def log(self):
         logging.info('Node manager : %u nodes', len(self._node_set))
         if self._node_set:
             logging.info('\n'.join(formatNodeList(
                 map(Node.asTuple, self._node_set), ' * ')))
+        self.logQueuedEvents()
 
 @apply
 def NODE_TYPE_MAPPING():

neo/lib/protocol.py

@@ -20,7 +20,7 @@ import traceback
 from cStringIO import StringIO
 from struct import Struct
 
-PROTOCOL_VERSION = 9
+PROTOCOL_VERSION = 10
 
 # Size restrictions.
 MIN_PACKET_SIZE = 10
@@ -71,11 +71,11 @@ def ErrorCodes():
     OID_DOES_NOT_EXIST
     PROTOCOL_ERROR
     BROKEN_NODE
-    ALREADY_PENDING
     REPLICATION_ERROR
     CHECKING_ERROR
     BACKEND_NOT_IMPLEMENTED
     READ_ONLY_ACCESS
+    INCOMPLETE_TRANSACTION
 
 @Enum
 def ClusterStates():
@@ -146,12 +146,6 @@ def CellStates():
     # readable nor writable.
     CORRUPTED
 
-@Enum
-def LockState():
-    NOT_LOCKED
-    GRANTED
-    GRANTED_TO_OTHER
-
 # used for logging
 node_state_prefix_dict = {
     NodeStates.RUNNING: 'R',
@@ -404,6 +398,19 @@ class PStructItemOrNone(PStructItem):
         value = reader(self.size)
         return None if value == self._None else self.unpack(value)[0]
 
+class POption(PStruct):
+
+    def _encode(self, writer, value):
+        if value is None:
+            writer('\0')
+        else:
+            writer('\1')
+            PStruct._encode(self, writer, value)
+
+    def _decode(self, reader):
+        if '\0\1'.index(reader(1)):
+            return PStruct._decode(self, reader)
+
 class PList(PStructItem):
     """
         A list of homogeneous items
@@ -869,6 +876,18 @@ class BeginTransaction(Packet):
         PTID('tid'),
     )
 
+class FailedVote(Packet):
+    """
+    Report storage nodes for which vote failed. C -> M
+    True is returned if it's still possible to finish the transaction.
+    """
+    _fmt = PStruct('failed_vote',
+        PTID('tid'),
+        PFUUIDList,
+    )
+
+    _answer = Error
+
 class FinishTransaction(Packet):
     """
     Finish a transaction. C -> PM.
@@ -943,14 +962,60 @@ class GenerateOIDs(Packet):
         PFOidList,
     )
 
+class Deadlock(Packet):
+    """
+    Ask master to generate a new TTID that will be used by the client
+    to rebase a transaction. S -> PM -> C
+    """
+    _fmt = PStruct('notify_deadlock',
+        PTID('ttid'),
+        PTID('locking_tid'),
+    )
+
+class RebaseTransaction(Packet):
+    """
+    Rebase transaction. C -> S.
+    """
+    _fmt = PStruct('ask_rebase_transaction',
+        PTID('ttid'),
+        PTID('locking_tid'),
+    )
+
+    _answer = PStruct('answer_rebase_transaction',
+        PFOidList,
+    )
+
+class RebaseObject(Packet):
+    """
+    Rebase object. C -> S.
+
+    XXX: It is a request packet to simplify the implementation. For more
+         efficiency, this should be turned into a notification, and the
+         RebaseTransaction should answered once all objects are rebased
+         (so that the client can still wait on something).
+    """
+    _fmt = PStruct('ask_rebase_object',
+        PTID('ttid'),
+        PTID('oid'),
+    )
+
+    _answer = PStruct('answer_rebase_object',
+        POption('conflict',
+            PTID('serial'),
+            PTID('conflict_serial'),
+            POption('data',
+                PBoolean('compression'),
+                PChecksum('checksum'),
+                PString('data'),
+            ),
+        )
+    )
+
 class StoreObject(Packet):
     """
     Ask to store an object. Send an OID, an original serial, a current
     transaction ID, and data. C -> S.
-    Answer if an object has been stored. If an object is in conflict,
-    a serial of the conflicting transaction is returned. In this case,
-    if this serial is newer than the current transaction ID, a client
-    node must not try to resolve the conflict. S -> C.
+    As for IStorage, 'serial' is ZERO_TID for new objects.
     """
     _fmt = PStruct('ask_store_object',
         POID('oid'),
@@ -960,21 +1025,19 @@ class StoreObject(Packet):
         PString('data'),
         PTID('data_serial'),
         PTID('tid'),
-        PBoolean('unlock'),
     )
 
     _answer = PStruct('answer_store_object',
-        PBoolean('conflicting'),
-        POID('oid'),
-        PTID('serial'),
+        PTID('conflict'),
     )
 
 class AbortTransaction(Packet):
     """
-    Abort a transaction. C -> S, PM.
+    Abort a transaction. C -> PM -> S.
     """
     _fmt = PStruct('abort_transaction',
         PTID('tid'),
+        PFUUIDList, # unused for PM -> S
     )
 
 class StoreTransaction(Packet):
@@ -1158,6 +1221,7 @@ class NotifyNodeInformation(Packet):
     Notify information about one or more nodes. PM -> Any.
     """
     _fmt = PStruct('notify_node_informations',
+        PFloat('id_timestamp'),
         PFNodeList,
     )
 
@@ -1243,22 +1307,6 @@ class ObjectUndoSerial(Packet):
         ),
     )
 
-class HasLock(Packet):
-    """
-    Ask a storage is oid is locked by another transaction.
-    C -> S
-    Answer whether a transaction holds the write lock for requested object.
-    """
-    _fmt = PStruct('has_load_lock',
-        PTID('tid'),
-        POID('oid'),
-    )
-
-    _answer = PStruct('answer_has_lock',
-        POID('oid'),
-        PEnum('lock_state', LockState),
-    )
-
 class CheckCurrentSerial(Packet):
     """
     Verifies if given serial is current for object oid in the database, and
@@ -1270,16 +1318,12 @@ class CheckCurrentSerial(Packet):
     """
     _fmt = PStruct('ask_check_current_serial',
         PTID('tid'),
-        PTID('serial'),
-        POID('oid'),
-    )
-
-    _answer = PStruct('answer_store_object',
-        PBoolean('conflicting'),
         POID('oid'),
         PTID('serial'),
     )
 
+    _answer = StoreObject._answer
+
 class Pack(Packet):
     """
     Request a pack at given TID.
@@ -1661,6 +1705,8 @@ class Packets(dict):
                     ValidateTransaction)
     AskBeginTransaction, AnswerBeginTransaction = register(
                     BeginTransaction)
+    FailedVote = register(
+                    FailedVote)
     AskFinishTransaction, AnswerTransactionFinished = register(
                     FinishTransaction, ignore_when_closed=False)
     AskLockInformation, AnswerInformationLocked = register(
@@ -1671,6 +1717,12 @@ class Packets(dict):
                     UnlockInformation)
     AskNewOIDs, AnswerNewOIDs = register(
                     GenerateOIDs)
+    NotifyDeadlock = register(
+                    Deadlock)
+    AskRebaseTransaction, AnswerRebaseTransaction = register(
+                    RebaseTransaction)
+    AskRebaseObject, AnswerRebaseObject = register(
+                    RebaseObject)
     AskStoreObject, AnswerStoreObject = register(
                     StoreObject)
     AbortTransaction = register(
@@ -1709,8 +1761,6 @@ class Packets(dict):
                     ClusterState)
     AskObjectUndoSerial, AnswerObjectUndoSerial = register(
                     ObjectUndoSerial)
-    AskHasLock, AnswerHasLock = register(
-                    HasLock)
     AskTIDsFrom, AnswerTIDsFrom = register(
                     TIDListFrom)
     AskPack, AnswerPack = register(
@@ -1780,3 +1830,8 @@ def formatNodeList(node_list, prefix='', _sort_key=itemgetter(2)):
                     for i in xrange(len(node_list[0]) - 1))
         return map((prefix + t + '%s').__mod__, node_list)
     return ()
+
+NotifyNodeInformation._neolog = staticmethod(lambda timestamp, node_list:
+    ((timestamp,), formatNodeList(node_list, ' ! ')))
+
+Error._neolog = staticmethod(lambda *args: ((), ("%s (%s)" % args,)))

neo/lib/pt.py

@@ -258,15 +258,16 @@ class PartitionTable(object):
         partition on the line (here, line length is 11 to keep the docstring
         width under 80 column).
         """
+        node_list = sorted(self.count_dict)
         result = ['pt: node %u: %s, %s' % (i, uuid_str(node.getUUID()),
                      protocol.node_state_prefix_dict[node.getState()])
-                  for i, node in enumerate(sorted(self.count_dict))]
+                  for i, node in enumerate(node_list)]
         append = result.append
         line = []
         max_line_len = 20 # XXX: hardcoded number of partitions per line
         prefix = 0
         prefix_len = int(math.ceil(math.log10(self.np)))
-        for offset, row in enumerate(self.formatRows()):
+        for offset, row in enumerate(self._formatRows(node_list)):
             if len(line) == max_line_len:
                 append('pt: %0*u: %s' % (prefix_len, prefix, '|'.join(line)))
                 line = []
@@ -276,8 +277,7 @@ class PartitionTable(object):
             append('pt: %0*u: %s' % (prefix_len, prefix, '|'.join(line)))
         return result
 
-    def formatRows(self):
-        node_list = sorted(self.count_dict)
+    def _formatRows(self, node_list):
         cell_state_dict = protocol.cell_state_prefix_dict
         for row in self.partition_list:
             if row is None:
@@ -287,12 +287,14 @@ class PartitionTable(object):
                              for x in row}
                 yield ''.join(cell_dict.get(x, '.') for x in node_list)
 
-    def operational(self):
+    def operational(self, exclude_list=()):
         if not self.filled():
             return False
         for row in self.partition_list:
             for cell in row:
-                if cell.isReadable() and cell.getNode().isRunning():
+                if cell.isReadable():
+                    node = cell.getNode()
+                    if node.isRunning() and node.getUUID() not in exclude_list:
                         break
             else:
                 return False

neo/lib/threaded_app.py

@@ -17,9 +17,8 @@
 import thread, threading, weakref
 from . import logging
 from .app import BaseApplication
-from .connection import ConnectionClosed
 from .debug import register as registerLiveDebugger
-from .dispatcher import Dispatcher, ForgottenPacket
+from .dispatcher import Dispatcher
 from .locking import SimpleQueue
 
 class app_set(weakref.WeakSet):
@@ -141,17 +140,8 @@ class ThreadedApplication(BaseApplication):
         _handlePacket = self._handlePacket
         while True:
             qconn, qpacket, kw = get(True)
-            is_forgotten = isinstance(qpacket, ForgottenPacket)
-            if conn is qconn:
-                # check fake packet
-                if qpacket is None:
-                    raise ConnectionClosed
-                if msg_id == qpacket.getId():
-                    if is_forgotten:
-                        raise ValueError, 'ForgottenPacket for an ' \
-                            'explicitly expected packet.'
+            if conn is qconn and msg_id == qpacket.getId():
                 _handlePacket(qconn, qpacket, kw, handler)
                 break
-            if not is_forgotten and qpacket is not None:
             _handlePacket(qconn, qpacket, kw)
         return self.getHandlerData()

neo/master/app.py

@@ -29,6 +29,16 @@ from neo.lib.exception import ElectionFailure, PrimaryFailure, StoppedOperation
 
 class StateChangedException(Exception): pass
 
+_previous_time = 0
+def monotonic_time():
+    global _previous_time
+    now = time()
+    if _previous_time < now:
+        _previous_time = now
+    else:
+        _previous_time = now = _previous_time + 1e-3
+    return now
+
 from .backup_app import BackupApplication
 from .handlers import election, identification, secondary
 from .handlers import administration, client, storage
@@ -41,6 +51,7 @@ from .verification import VerificationManager
 class Application(BaseApplication):
     """The master node application."""
     packing = None
+    storage_readiness = 0
     # Latest completely committed TID
     last_transaction = ZERO_TID
     backup_tid = None
@@ -56,7 +67,7 @@ class Application(BaseApplication):
         self.server = config.getBind()
         self.autostart = config.getAutostart()
 
-        self.storage_readiness = set()
+        self.storage_ready_dict = {}
         for master_address in config.getMasters():
             self.nm.createMaster(address=master_address)
 
@@ -240,11 +251,12 @@ class Application(BaseApplication):
                 continue
             node_dict[NodeTypes.MASTER].append(node_info)
 
+        now = monotonic_time()
         # send at most one non-empty notification packet per node
         for node in self.nm.getIdentifiedList():
             node_list = node_dict.get(node.getType())
             if node_list and node.isRunning() and node is not exclude:
-                node.notify(Packets.NotifyNodeInformation(node_list))
+                node.notify(Packets.NotifyNodeInformation(now, node_list))
 
     def broadcastPartitionChanges(self, cell_list):
         """Broadcast a Notify Partition Changes packet."""
@@ -398,6 +410,7 @@ class Application(BaseApplication):
                 conn.close()
 
         # Reconnect to primary master node.
+        self.nm.reset()
         primary_handler = secondary.PrimaryHandler(self)
         ClientConnection(self, primary_handler, self.primary_master_node)
 
@@ -491,11 +504,12 @@ class Application(BaseApplication):
 
         logging.info("asking remaining nodes to shutdown")
         handler = EventHandler(self)
+        now = monotonic_time()
         for node in self.nm.getConnectedList():
             conn = node.getConnection()
             if node.isStorage():
                 conn.setHandler(handler)
-                conn.notify(Packets.NotifyNodeInformation(((
+                conn.notify(Packets.NotifyNodeInformation(now, ((
                   node.getType(), node.getAddress(), node.getUUID(),
                   NodeStates.TEMPORARILY_DOWN, None),)))
                 conn.abort()
@@ -561,11 +575,16 @@ class Application(BaseApplication):
         self.last_transaction = tid
 
     def setStorageNotReady(self, uuid):
-        self.storage_readiness.discard(uuid)
+        self.storage_ready_dict.pop(uuid, None)
 
     def setStorageReady(self, uuid):
-        self.storage_readiness.add(uuid)
+        if uuid not in self.storage_ready_dict:
+            self.storage_readiness = self.storage_ready_dict[uuid] = \
+                self.storage_readiness + 1
 
     def isStorageReady(self, uuid):
-        return uuid in self.storage_readiness
+        return uuid in self.storage_ready_dict
 
+    def getStorageReadySet(self, readiness=float('inf')):
+        return {k for k, v in self.storage_ready_dict.iteritems()
+                  if v <= readiness}

neo/master/handlers/__init__.py

@@ -14,6 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from ..app import monotonic_time
 from neo.lib import logging
 from neo.lib.exception import StoppedOperation
 from neo.lib.handler import EventHandler
@@ -88,7 +89,7 @@ class MasterHandler(EventHandler):
         node_list.extend(n.asTuple() for n in nm.getMasterList())
         node_list.extend(n.asTuple() for n in nm.getClientList())
         node_list.extend(n.asTuple() for n in nm.getStorageList())
-        conn.notify(Packets.NotifyNodeInformation(node_list))
+        conn.notify(Packets.NotifyNodeInformation(monotonic_time(), node_list))
 
     def askPartitionTable(self, conn):
         pt = self.app.pt

neo/master/handlers/administration.py

@@ -17,7 +17,7 @@
 import random
 
 from . import MasterHandler
-from ..app import StateChangedException
+from ..app import monotonic_time, StateChangedException
 from neo.lib import logging
 from neo.lib.exception import StoppedOperation
 from neo.lib.pt import PartitionTableException
@@ -103,7 +103,8 @@ class AdministrationHandler(MasterHandler):
             node.setState(state)
             if node.isConnected():
                 # notify itself so it can shutdown
-                node.notify(Packets.NotifyNodeInformation([node.asTuple()]))
+                node.notify(Packets.NotifyNodeInformation(
+                    monotonic_time(), [node.asTuple()]))
                 # close to avoid handle the closure as a connection lost
                 node.getConnection().abort()
             if keep:
@@ -121,7 +122,8 @@ class AdministrationHandler(MasterHandler):
             # ignores non-running nodes
             assert not node.isRunning()
             if node.isConnected():
-                node.notify(Packets.NotifyNodeInformation([node.asTuple()]))
+                node.notify(Packets.NotifyNodeInformation(
+                    monotonic_time(), [node.asTuple()]))
             app.broadcastNodesInformation([node])
 
     def addPendingNodes(self, conn, uuid_list):

neo/master/handlers/client.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from neo.lib.protocol import NodeStates, Packets, ProtocolError, MAX_TID, Errors
+from ..app import monotonic_time
 from . import MasterHandler
 
 class ClientServiceHandler(MasterHandler):
@@ -36,7 +37,7 @@ class ClientServiceHandler(MasterHandler):
         node_list = [nm.getByUUID(conn.getUUID()).asTuple()] # for id_timestamp
         node_list.extend(n.asTuple() for n in nm.getMasterList())
         node_list.extend(n.asTuple() for n in nm.getStorageList())
-        conn.notify(Packets.NotifyNodeInformation(node_list))
+        conn.notify(Packets.NotifyNodeInformation(monotonic_time(), node_list))
 
     def askBeginTransaction(self, conn, tid):
         """
@@ -44,46 +45,42 @@ class ClientServiceHandler(MasterHandler):
         """
         app = self.app
         node = app.nm.getByUUID(conn.getUUID())
-        conn.answer(Packets.AnswerBeginTransaction(app.tm.begin(node, tid)))
+        tid = app.tm.begin(node, app.storage_readiness, tid)
+        conn.answer(Packets.AnswerBeginTransaction(tid))
 
     def askNewOIDs(self, conn, num_oids):
         conn.answer(Packets.AnswerNewOIDs(self.app.tm.getNextOIDList(num_oids)))
 
+    def getEventQueue(self):
+        # for failedVote
+        return self.app.tm
+
+    def failedVote(self, conn, *args):
+        app = self.app
+        conn.answer((Errors.Ack if app.tm.vote(app, *args) else
+                     Errors.IncompleteTransaction)())
+
     def askFinishTransaction(self, conn, ttid, oid_list, checked_list):
         app = self.app
-        pt = app.pt
-
-        # Collect partitions related to this transaction.
-        getPartition = pt.getPartition
-        partition_set = set(map(getPartition, oid_list))
-        partition_set.update(map(getPartition, checked_list))
-        partition_set.add(getPartition(ttid))
-
-        # Collect the UUIDs of nodes related to this transaction.
-        uuid_list = filter(app.isStorageReady, {cell.getUUID()
-            for part in partition_set
-            for cell in pt.getCellList(part)
-            if cell.getNodeState() != NodeStates.HIDDEN})
-        if not uuid_list:
-            raise ProtocolError('No storage node ready for transaction')
-
-        identified_node_list = app.nm.getIdentifiedList(pool_set=set(uuid_list))
-
-        # Request locking data.
-        # build a new set as we may not send the message to all nodes as some
-        # might be not reachable at that time
-        p = Packets.AskLockInformation(
+        tid, node_list = app.tm.prepare(
+            app,
             ttid,
-            app.tm.prepare(
-                ttid,
-                pt.getPartitions(),
             oid_list,
-                {x.getUUID() for x in identified_node_list},
+            checked_list,
             conn.getPeerId(),
-            ),
         )
-        for node in identified_node_list:
+        if tid:
+            p = Packets.AskLockInformation(ttid, tid)
+            for node in node_list:
                 node.ask(p, timeout=60)
+        else:
+            conn.answer(Errors.IncompleteTransaction())
+            # It's simpler to abort automatically rather than asking the client
+            # to send a notification on tpc_abort, since it would have keep the
+            # transaction longer in list of transactions.
+            # This should happen so rarely that we don't try to minimize the
+            # number of abort notifications by looking the modified partitions.
+            self.abortTransaction(conn, ttid, app.getStorageReadySet())
 
     def askFinalTID(self, conn, ttid):
         tm = self.app.tm
@@ -112,9 +109,24 @@ class ClientServiceHandler(MasterHandler):
         else:
             conn.answer(Packets.AnswerPack(False))
 
-    def abortTransaction(self, conn, tid):
-        # BUG: The replicator may wait this transaction to be finished.
-        self.app.tm.abort(tid, conn.getUUID())
+    def abortTransaction(self, conn, tid, uuid_list):
+        # Consider a failure when the connection between the storage and the
+        # client breaks while the answer to the first write is sent back.
+        # In other words, the client can not know the exact set of nodes that
+        # know this transaction, and it sends us all nodes it considered for
+        # writing.
+        # We must also add those that are waiting for this transaction to be
+        # finished (returned by tm.abort), because they may have join the
+        # cluster after that the client started to abort.
+        app = self.app
+        involved = app.tm.abort(tid, conn.getUUID())
+        involved.update(uuid_list)
+        involved.intersection_update(app.getStorageReadySet())
+        if involved:
+            p = Packets.AbortTransaction(tid, ())
+            getByUUID = app.nm.getByUUID
+            for involved in involved:
+                getByUUID(involved).notify(p)
 
 
 # like ClientServiceHandler but read-only & only for tid <= backup_tid

neo/master/handlers/election.py

@@ -56,7 +56,7 @@ class BaseElectionHandler(EventHandler):
 
 class ClientElectionHandler(BaseElectionHandler):
 
-    def notifyNodeInformation(self, conn, node_list):
+    def notifyNodeInformation(self, conn, timestamp, node_list):
         # XXX: For the moment, do nothing because
         # we'll close this connection and reconnect.
         pass

neo/master/handlers/identification.py

@@ -14,10 +14,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from time import time
 from neo.lib import logging
 from neo.lib.protocol import ClusterStates, NodeStates, NodeTypes, \
     NotReadyError, ProtocolError, uuid_str
+from ..app import monotonic_time
 from . import MasterHandler
 
 class IdentificationHandler(MasterHandler):
@@ -92,7 +92,7 @@ class IdentificationHandler(MasterHandler):
                 uuid=uuid, address=address)
         else:
             node.setUUID(uuid)
-        node.id_timestamp = time()
+        node.id_timestamp = monotonic_time()
         node.setState(state)
         node.setConnection(conn)
         conn.setHandler(handler)

neo/master/handlers/secondary.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import sys
+from ..app import monotonic_time
 from . import MasterHandler
 from neo.lib.handler import EventHandler
 from neo.lib.exception import ElectionFailure, PrimaryFailure
@@ -38,7 +39,7 @@ class SecondaryMasterHandler(MasterHandler):
 
     def _notifyNodeInformation(self, conn):
         node_list = [n.asTuple() for n in self.app.nm.getMasterList()]
-        conn.notify(Packets.NotifyNodeInformation(node_list))
+        conn.notify(Packets.NotifyNodeInformation(monotonic_time(), node_list))
 
 class PrimaryHandler(EventHandler):
     """ Handler used by secondaries to handle primary master"""
@@ -72,8 +73,9 @@ class PrimaryHandler(EventHandler):
     def notifyClusterInformation(self, conn, state):
         self.app.cluster_state = state
 
-    def notifyNodeInformation(self, conn, node_list):
-        super(PrimaryHandler, self).notifyNodeInformation(conn, node_list)
+    def notifyNodeInformation(self, conn, timestamp, node_list):
+        super(PrimaryHandler, self).notifyNodeInformation(
+            conn, timestamp, node_list)
         for node_type, _, uuid, state, _ in node_list:
             assert node_type == NodeTypes.MASTER, node_type
             if uuid == self.app.uuid and state == NodeStates.UNKNOWN:

neo/master/handlers/storage.py

@@ -26,18 +26,18 @@ class StorageServiceHandler(BaseServiceHandler):
 
     def connectionCompleted(self, conn, new):
         app = self.app
-        uuid = conn.getUUID()
-        app.setStorageNotReady(uuid)
         if new:
             super(StorageServiceHandler, self).connectionCompleted(conn, new)
-        if app.nm.getByUUID(uuid).isRunning(): # node may be PENDING
+        if app.nm.getByUUID(conn.getUUID()).isRunning(): # node may be PENDING
             conn.notify(Packets.StartOperation(app.backup_tid))
 
     def connectionLost(self, conn, new_state):
         app = self.app
-        node = app.nm.getByUUID(conn.getUUID())
+        uuid = conn.getUUID()
+        node = app.nm.getByUUID(uuid)
         super(StorageServiceHandler, self).connectionLost(conn, new_state)
-        app.tm.storageLost(conn.getUUID())
+        app.setStorageNotReady(uuid)
+        app.tm.storageLost(uuid)
         if (app.getClusterState() == ClusterStates.BACKINGUP
             # Also check if we're exiting, because backup_app is not usable
             # in this case. Maybe cluster state should be set to something
@@ -61,6 +61,9 @@ class StorageServiceHandler(BaseServiceHandler):
         p = Packets.AnswerUnfinishedTransactions(last_tid, pending_list)
         conn.answer(p)
 
+    def notifyDeadlock(self, conn, *args):
+        self.app.tm.deadlock(conn.getUUID(), *args)
+
     def answerInformationLocked(self, conn, ttid):
         self.app.tm.lock(ttid, conn.getUUID())
 

neo/master/recovery.py

@@ -16,6 +16,7 @@
 
 from neo.lib import logging
 from neo.lib.protocol import Packets, ProtocolError, ClusterStates, NodeStates
+from .app import monotonic_time
 from .handlers import MasterHandler
 
 
@@ -170,7 +171,8 @@ class RecoveryManager(MasterHandler):
                 new_nodes = app.pt.load(ptid, row_list, app.nm)
             except IndexError:
                 raise ProtocolError('Invalid offset')
-            self._notifyAdmins(Packets.NotifyNodeInformation(new_nodes),
+            self._notifyAdmins(
+                Packets.NotifyNodeInformation(monotonic_time(), new_nodes),
                 Packets.SendPartitionTable(ptid, row_list))
             self.ask_pt = ()
             uuid = conn.getUUID()

neo/master/transactions.py

@@ -18,29 +18,31 @@ from collections import deque
 from time import time
 from struct import pack, unpack
 from neo.lib import logging
-from neo.lib.protocol import ProtocolError, uuid_str, ZERO_OID, ZERO_TID
+from neo.lib.handler import DelayEvent, EventQueue
+from neo.lib.protocol import Packets, ProtocolError, uuid_str, \
+    ZERO_OID, ZERO_TID
 from neo.lib.util import dump, u64, addTID, tidFromTime
 
-class DelayedError(Exception):
-    pass
-
 class Transaction(object):
     """
         A pending transaction
     """
+    locking_tid = ZERO_TID
     _tid = None
     _msg_id = None
     _oid_list = None
+    _failed = frozenset()
     _prepared = False
     # uuid dict hold flag to known who has locked the transaction
     _uuid_set = None
     _lock_wait_uuid_set = None
 
-    def __init__(self, node, ttid):
+    def __init__(self, node, storage_readiness, ttid):
         """
             Prepare the transaction, set OIDs and UUIDs related to it
         """
         self._node = node
+        self._storage_readiness = storage_readiness
         self._ttid = ttid
         self._birth = time()
         # store storage uuids that must be notified at commit
@@ -113,13 +115,13 @@ class Transaction(object):
         """
         return list(self._notification_set)
 
-    def prepare(self, tid, oid_list, uuid_list, msg_id):
+    def prepare(self, tid, oid_list, uuid_set, msg_id):
 
         self._tid = tid
         self._oid_list = oid_list
         self._msg_id = msg_id
-        self._uuid_set = set(uuid_list)
-        self._lock_wait_uuid_set = set(uuid_list)
+        self._uuid_set = uuid_set
+        self._lock_wait_uuid_set = uuid_set.copy()
         self._prepared = True
 
     def storageLost(self, uuid):
@@ -163,7 +165,7 @@ class Transaction(object):
         return not self._lock_wait_uuid_set
 
 
-class TransactionManager(object):
+class TransactionManager(EventQueue):
     """
         Manage current transactions
     """
@@ -173,6 +175,7 @@ class TransactionManager(object):
         self.reset()
 
     def reset(self):
+        EventQueue.__init__(self)
         # ttid -> transaction
         self._ttid_dict = {}
         self._last_oid = ZERO_OID
@@ -195,6 +198,7 @@ class TransactionManager(object):
         except ValueError:
             pass
         del self._ttid_dict[ttid]
+        self.executeQueuedEvents()
 
     def __contains__(self, ttid):
         """
@@ -285,7 +289,7 @@ class TransactionManager(object):
             txn.registerForNotification(uuid)
         return self._ttid_dict.keys()
 
-    def begin(self, node, tid=None):
+    def begin(self, node, storage_readiness, tid=None):
         """
             Generate a new TID
         """
@@ -297,38 +301,116 @@ class TransactionManager(object):
             # last TID.
             self._queue.append(tid)
             self.setLastTID(tid)
-        txn = self._ttid_dict[tid] = Transaction(node, tid)
+        txn = self._ttid_dict[tid] = Transaction(node, storage_readiness, tid)
         logging.debug('Begin %s', txn)
         return tid
 
-    def prepare(self, ttid, divisor, oid_list, uuid_list, msg_id):
+    def deadlock(self, storage_id, ttid, locking_tid):
+        try:
+            txn = self._ttid_dict[ttid]
+        except KeyError:
+            return
+        if txn.locking_tid <= locking_tid:
+            client = txn.getNode()
+            txn.locking_tid = locking_tid = self._nextTID()
+            logging.info('Deadlock avoidance triggered by %s for %s:'
+                ' new locking tid for TXN %s is %s', uuid_str(storage_id),
+                uuid_str(client.getUUID()), dump(ttid), dump(locking_tid))
+            client.notify(Packets.NotifyDeadlock(ttid, locking_tid))
+
+    def vote(self, app, ttid, uuid_list):
+        """
+            Check that the transaction can be voted
+            when the client reports failed nodes.
+        """
+        txn = self[ttid]
+        # The client does not know which nodes are not expected to have
+        # transactions in full. Let's filter out them.
+        failed = app.getStorageReadySet(txn._storage_readiness)
+        failed.intersection_update(uuid_list)
+        if failed:
+            operational = app.pt.operational
+            if not operational(failed):
+                # No way to commit this transaction because there are
+                # non-replicated storage nodes with failed stores.
+                return False
+            failed = failed.copy()
+            for t in self._ttid_dict.itervalues():
+                failed |= t._failed
+            if not operational(failed):
+                # Other transactions were voted and unless they're aborted,
+                # we won't be able to finish this one, because that would make
+                # the cluster non-operational. Let's tell the caller to retry
+                # later.
+                raise DelayEvent
+            # Allow the client to finish the transaction,
+            # even if it will disconnect storage nodes.
+            txn._failed = failed
+        return True
+
+    def prepare(self, app, ttid, oid_list, checked_list, msg_id):
         """
             Prepare a transaction to be finished
         """
         txn = self[ttid]
+        pt = app.pt
+
+        failed = txn._failed
+        if failed and not pt.operational(failed):
+            return None, None
+        ready = app.getStorageReadySet(txn._storage_readiness)
+        getPartition = pt.getPartition
+        partition_set = set(map(getPartition, oid_list))
+        partition_set.update(map(getPartition, checked_list))
+        partition_set.add(getPartition(ttid))
+        node_list = []
+        uuid_set = set()
+        for partition in partition_set:
+            for cell in pt.getCellList(partition):
+                node = cell.getNode()
+                if node.isIdentified():
+                    uuid = node.getUUID()
+                    if uuid in uuid_set:
+                        continue
+                    if uuid in failed:
+                        # This will commit a new PT with outdated cells before
+                        # locking the transaction, which is important during
+                        # the verification phase.
+                        node.getConnection().close()
+                    elif uuid in ready:
+                        uuid_set.add(uuid)
+                        node_list.append(node)
+        # A node that was not ready at the beginning of the transaction
+        # can't have readable cells. And if we're still operational without
+        # the 'failed' nodes, then there must still be 1 node in 'ready'
+        # that is UP.
+        assert node_list, (ready, failed)
+
         # maybe not the fastest but _queue should be often small
         if ttid in self._queue:
             tid = ttid
         else:
-            tid = self._nextTID(ttid, divisor)
+            tid = self._nextTID(ttid, pt.getPartitions())
             self._queue.append(ttid)
         logging.debug('Finish TXN %s for %s (was %s)',
                       dump(tid), txn.getNode(), dump(ttid))
-        txn.prepare(tid, oid_list, uuid_list, msg_id)
+        txn.prepare(tid, oid_list, uuid_set, msg_id)
         # check if greater and foreign OID was stored
         if oid_list:
             self.setLastOID(max(oid_list))
-        return tid
+        return tid, node_list
 
     def abort(self, ttid, uuid):
         """
             Abort a transaction
         """
         logging.debug('Abort TXN %s for %s', dump(ttid), uuid_str(uuid))
-        if self[ttid].isPrepared():
+        txn = self[ttid]
+        if txn.isPrepared():
             raise ProtocolError("commit already requested for ttid %s"
                                 % dump(ttid))
         del self[ttid]
+        return txn._notification_set
 
     def lock(self, ttid, uuid):
         """
@@ -350,7 +432,7 @@ class TransactionManager(object):
         for ttid, txn in self._ttid_dict.iteritems():
             if txn.storageLost(uuid) and self._queue[0] == ttid:
                 unlock = True
-                # do not break: we must call forget() on all transactions
+                # do not break: we must call storageLost() on all transactions
         if unlock:
             self._unlockPending()
 
@@ -370,6 +452,7 @@ class TransactionManager(object):
                 break
             del queue[0], self._ttid_dict[ttid]
             self._on_commit(txn)
+        self.executeQueuedEvents()
 
     def clientLost(self, node):
         for txn in self._ttid_dict.values():
@@ -380,4 +463,4 @@ class TransactionManager(object):
         logging.info('Transactions:')
         for txn in self._ttid_dict.itervalues():
             logging.info('  %r', txn)
-
+        self.logQueuedEvents()

neo/scripts/neolog.py

@@ -20,7 +20,6 @@
 import bz2, gzip, errno, optparse, os, signal, sqlite3, sys, time
 from bisect import insort
 from logging import getLevelName
-from functools import partial
 
 comp_dict = dict(bz2=bz2.BZ2File, gz=gzip.GzipFile)
 
@@ -94,11 +93,6 @@ class Log(object):
         exec bz2.decompress(text) in g
         for x in 'uuid_str', 'Packets', 'PacketMalformedError':
             setattr(self, x, g[x])
-        try:
-            self.notifyNodeInformation = partial(g['formatNodeList'],
-                                                 prefix=' ! ')
-        except KeyError:
-            self.notifyNodeInformation = None
         try:
             self._next_protocol, = q("SELECT date FROM protocol WHERE date>?",
                                      (date,)).next()
@@ -131,8 +125,8 @@ class Log(object):
             body = None
         msg = ['#0x%04x %-30s %s' % (msg_id, msg, peer)]
         if body is not None:
-            logger = getattr(self, p.handler_method_name, None)
-            if logger or self._decode_all:
+            log = getattr(p, '_neolog', None)
+            if log or self._decode_all:
                 p = p()
                 p._id = msg_id
                 p._body = body
@@ -141,15 +135,13 @@ class Log(object):
                 except self.PacketMalformedError:
                     msg.append("Can't decode packet")
                 else:
-                    if logger:
-                        msg += logger(*args)
-                    elif args:
-                        msg = '%s \t| %r' % (msg[0], args),
+                    if log:
+                        args, extra = log(*args)
+                        msg += extra
+                    if args and self._decode_all:
+                        msg[0] += ' \t| ' + repr(args)
         return date, name, 'PACKET', msg
 
-    def error(self, code, message):
-        return "%s (%s)" % (code, message),
-
 
 def emit_many(log_list):
     log_list = [(log, iter(log).next) for log in log_list]

neo/scripts/runner.py

@@ -46,7 +46,6 @@ UNIT_TEST_MODULES = [
     'neo.tests.testConnection',
     'neo.tests.testHandler',
     'neo.tests.testNodes',
-    'neo.tests.testDispatcher',
     'neo.tests.testUtil',
     'neo.tests.testPT',
     # master application

neo/storage/app.py

@@ -28,7 +28,6 @@ from neo.lib.util import dump
 from neo.lib.bootstrap import BootstrapManager
 from .checker import Checker
 from .database import buildDatabaseManager
-from .exception import AlreadyPendingError
 from .handlers import identification, initialization
 from .handlers import master, hidden
 from .replicator import Replicator
@@ -39,13 +38,14 @@ from neo.lib.debug import register as registerLiveDebugger
 class Application(BaseApplication):
     """The storage node application."""
 
+    tm = None
+
     def __init__(self, config):
         super(Application, self).__init__(
             config.getSSL(), config.getDynamicMasterList())
         # set the cluster name
         self.name = config.getCluster()
 
-        self.tm = TransactionManager(self)
         self.dm = buildDatabaseManager(config.getAdapter(),
             (config.getDatabase(), config.getEngine(), config.getWait()),
         )
@@ -69,8 +69,6 @@ class Application(BaseApplication):
         self.master_node = None
 
         # operation related data
-        self.event_queue = None
-        self.event_queue_dict = None
         self.operational = False
 
         # ready is True when operational and got all informations
@@ -95,8 +93,8 @@ class Application(BaseApplication):
 
     def log(self):
         self.em.log()
-        self.logQueuedEvents()
         self.nm.log()
+        if self.tm:
             self.tm.log()
         if self.pt is not None:
             self.pt.log()
@@ -188,9 +186,7 @@ class Application(BaseApplication):
             for conn in self.em.getConnectionList():
                 if conn not in (self.listening_conn, self.master_conn):
                     conn.close()
-            # create/clear event queue
-            self.event_queue = deque()
-            self.event_queue_dict = {}
+            self.tm = TransactionManager(self)
             try:
                 self.initialize()
                 self.doOperation()
@@ -201,6 +197,7 @@ class Application(BaseApplication):
                 logging.error('primary master is down: %s', msg)
             finally:
                 self.checker = Checker(self)
+            del self.tm
 
     def connectToPrimary(self):
         """Find a primary master node, and connect to it.
@@ -247,8 +244,8 @@ class Application(BaseApplication):
         while not self.operational:
             _poll()
         self.ready = True
-        self.replicator.populate()
         self.master_conn.notify(Packets.NotifyReady())
+        self.replicator.populate()
 
     def doOperation(self):
         """Handle everything, including replications and transactions."""
@@ -263,7 +260,6 @@ class Application(BaseApplication):
 
         # Forget all unfinished data.
         self.dm.dropUnfinishedData()
-        self.tm.reset()
 
         self.task_queue = task_queue = deque()
         try:
@@ -308,46 +304,6 @@ class Application(BaseApplication):
             if not node.isHidden():
                 break
 
-    def queueEvent(self, some_callable, conn=None, args=(), key=None,
-            raise_on_duplicate=True):
-        event_queue_dict = self.event_queue_dict
-        n = event_queue_dict.get(key)
-        if n and raise_on_duplicate:
-            raise AlreadyPendingError()
-        msg_id = None if conn is None else conn.getPeerId()
-        self.event_queue.append((key, some_callable, msg_id, conn, args))
-        if key is not None:
-            event_queue_dict[key] = n + 1 if n else 1
-
-    def executeQueuedEvents(self):
-        p = self.event_queue.popleft
-        event_queue_dict = self.event_queue_dict
-        for _ in xrange(len(self.event_queue)):
-            key, some_callable, msg_id, conn, args = p()
-            if key is not None:
-                n = event_queue_dict[key] - 1
-                if n:
-                    event_queue_dict[key] = n
-                else:
-                    del event_queue_dict[key]
-            if conn is None:
-                some_callable(*args)
-            elif not conn.isClosed():
-                orig_msg_id = conn.getPeerId()
-                try:
-                    conn.setPeerId(msg_id)
-                    some_callable(conn, *args)
-                finally:
-                    conn.setPeerId(orig_msg_id)
-
-    def logQueuedEvents(self):
-        if self.event_queue is None:
-            return
-        logging.info("Pending events:")
-        for key, event, _msg_id, _conn, args in self.event_queue:
-            logging.info('  %r:%r: %r:%r %r %r', key, event.__name__,
-                _msg_id, _conn, args)
-
     def newTask(self, iterator):
         try:
             iterator.next()

neo/storage/checker.py

@@ -109,7 +109,7 @@ class Checker(object):
         self.source = source
         def start():
             if app.tm.isLockedTid(max_tid):
-                app.queueEvent(start)
+                app.tm.queueEvent(start)
                 return
             args = partition, CHECK_COUNT, min_tid, max_tid
             p = Packets.AskCheckTIDRange(*args)

neo/storage/database/importer.py

@@ -304,7 +304,7 @@ class ImporterDatabaseManager(DatabaseManager):
                     getPartitionTable changePartitionTable
                     getUnfinishedTIDDict dropUnfinishedData abortTransaction
                     storeTransaction lockTransaction unlockTransaction
-                    storeData getOrphanList _pruneData deferCommit
+                    loadData storeData getOrphanList _pruneData deferCommit
                  """.split():
             setattr(self, x, getattr(self.db, x))
 

neo/storage/database/manager.py

@@ -463,6 +463,11 @@ class DatabaseManager(object):
         no hash collision.
         """
 
+    @abstract
+    def loadData(self, data_id):
+        """Inverse of storeData
+        """
+
     def holdData(self, checksum_or_id, *args):
         """Store raw data of temporary object
 

neo/storage/database/mysqldb.py

@@ -541,6 +541,15 @@ class MySQLDatabaseManager(DatabaseManager):
             raise
         return self.conn.insert_id()
 
+    def loadData(self, data_id):
+        compression, hash, value = self.query(
+            "SELECT compression, hash, value FROM data where id=%s"
+            % data_id)[0]
+        if compression and compression & 0x80:
+            compression &= 0x7f
+            data = ''.join(self._bigData(data))
+        return compression, hash, value
+
     del _structLL
 
     def _getDataTID(self, oid, tid=None, before_tid=None):

neo/storage/database/sqlite.py

@@ -404,6 +404,10 @@ class SQLiteDatabaseManager(DatabaseManager):
                     return r
             raise
 
+    def loadData(self, data_id):
+        return self.query("SELECT compression, hash, value"
+                          " FROM data where id=?", (data_id,)).fetchone()
+
     def _getDataTID(self, oid, tid=None, before_tid=None):
         partition = self._getPartition(oid)
         sql = 'SELECT tid, value_tid FROM obj' \

neo/storage/exception.py

-#
-# Copyright (C) 2010-2017  Nexedi SA
-#
-# This program is free software; you can redistribute it and/or
-# modify it under the terms of the GNU General Public License
-# as published by the Free Software Foundation; either version 2
-# of the License, or (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-class AlreadyPendingError(Exception):
-    pass
-

neo/storage/handlers/__init__.py

@@ -36,10 +36,11 @@ class BaseMasterHandler(EventHandler):
     def notifyClusterInformation(self, conn, state):
         self.app.changeClusterState(state)
 
-    def notifyNodeInformation(self, conn, node_list):
+    def notifyNodeInformation(self, conn, timestamp, node_list):
         """Store information on nodes, only if this is sent by a primary
         master node."""
-        super(BaseMasterHandler, self).notifyNodeInformation(conn, node_list)
+        super(BaseMasterHandler, self).notifyNodeInformation(
+            conn, timestamp, node_list)
         for node_type, _, uuid, state, _ in node_list:
             if uuid == self.app.uuid:
                 # This is me, do what the master tell me

neo/storage/handlers/client.py

@@ -15,12 +15,11 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from neo.lib import logging
-from neo.lib.handler import EventHandler
+from neo.lib.handler import DelayEvent, EventHandler
 from neo.lib.util import dump, makeChecksum, add64
-from neo.lib.protocol import Packets, LockState, Errors, ProtocolError, \
+from neo.lib.protocol import Packets, Errors, ProtocolError, \
     ZERO_HASH, INVALID_PARTITION
-from ..transactions import ConflictError, DelayedError, NotRegisteredError
-from ..exception import AlreadyPendingError
+from ..transactions import ConflictError, NotRegisteredError
 import time
 
 # Log stores taking (incl. lock delays) more than this many seconds.
@@ -38,12 +37,14 @@ class ClientOperationHandler(EventHandler):
                     t[4], t[0])
         conn.answer(p)
 
+    def getEventQueue(self):
+        # for read rpc
+        return self.app.tm
+
     def askObject(self, conn, oid, serial, tid):
         app = self.app
         if app.tm.loadLocked(oid):
-            # Delay the response.
-            app.queueEvent(self.askObject, conn, (oid, serial, tid))
-            return
+            raise DelayEvent
         o = app.dm.getObject(oid, serial, tid)
         try:
             serial, next_serial, compression, checksum, data, data_serial = o
@@ -58,9 +59,6 @@ class ClientOperationHandler(EventHandler):
                 compression, checksum, data, data_serial)
         conn.answer(p)
 
-    def abortTransaction(self, conn, ttid):
-        self.app.tm.abort(ttid)
-
     def askStoreTransaction(self, conn, ttid, *txn_info):
         self.app.tm.register(conn, ttid)
         self.app.tm.vote(ttid, txn_info)
@@ -71,41 +69,29 @@ class ClientOperationHandler(EventHandler):
         conn.answer(Packets.AnswerVoteTransaction())
 
     def _askStoreObject(self, conn, oid, serial, compression, checksum, data,
-            data_serial, ttid, unlock, request_time):
+            data_serial, ttid, request_time):
         try:
             self.app.tm.storeObject(ttid, serial, oid, compression,
-                    checksum, data, data_serial, unlock)
+                    checksum, data, data_serial)
         except ConflictError, err:
             # resolvable or not
-            conn.answer(Packets.AnswerStoreObject(1, oid, err.tid))
-        except DelayedError:
-            # locked by a previous transaction, retry later
-            # If we are unlocking, we want queueEvent to raise
-            # AlreadyPendingError, to avoid making client wait for an unneeded
-            # response.
-            try:
-                self.app.queueEvent(self._askStoreObject, conn, (oid, serial,
-                    compression, checksum, data, data_serial, ttid,
-                    unlock, request_time), key=(oid, ttid),
-                    raise_on_duplicate=unlock)
-            except AlreadyPendingError:
-                conn.answer(Errors.AlreadyPending(dump(oid)))
+            conn.answer(Packets.AnswerStoreObject(err.tid))
         except NotRegisteredError:
             # transaction was aborted, cancel this event
             logging.info('Forget store of %s:%s by %s delayed by %s',
                     dump(oid), dump(serial), dump(ttid),
                     dump(self.app.tm.getLockingTID(oid)))
             # send an answer as the client side is waiting for it
-            conn.answer(Packets.AnswerStoreObject(0, oid, serial))
+            conn.answer(Packets.AnswerStoreObject(None))
         else:
-            if SLOW_STORE is not None:
+            if request_time and SLOW_STORE is not None:
                 duration = time.time() - request_time
                 if duration > SLOW_STORE:
                     logging.info('StoreObject delay: %.02fs', duration)
-            conn.answer(Packets.AnswerStoreObject(0, oid, serial))
+            conn.answer(Packets.AnswerStoreObject(None))
 
     def askStoreObject(self, conn, oid, serial,
-            compression, checksum, data, data_serial, ttid, unlock):
+            compression, checksum, data, data_serial, ttid):
         if 1 < compression:
             raise ProtocolError('invalid compression value')
         # register the transaction
@@ -116,8 +102,33 @@ class ClientOperationHandler(EventHandler):
             assert data_serial is None
         else:
             checksum = data = None
-        self._askStoreObject(conn, oid, serial, compression, checksum, data,
-            data_serial, ttid, unlock, time.time())
+        try:
+            self._askStoreObject(conn, oid, serial, compression,
+                checksum, data, data_serial, ttid, None)
+        except DelayEvent:
+            # locked by a previous transaction, retry later
+            self.app.tm.queueEvent(self._askStoreObject, conn, (oid, serial,
+                compression, checksum, data, data_serial, ttid, time.time()))
+
+    def askRebaseTransaction(self, conn, *args):
+        conn.answer(Packets.AnswerRebaseTransaction(
+            self.app.tm.rebase(conn, *args)))
+
+    def askRebaseObject(self, conn, ttid, oid):
+        try:
+            self._askRebaseObject(conn, ttid, oid, None)
+        except DelayEvent:
+            # locked by a previous transaction, retry later
+            self.app.tm.queueEvent(self._askRebaseObject,
+                conn, (ttid, oid, time.time()))
+
+    def _askRebaseObject(self, conn, ttid, oid, request_time):
+        conflict = self.app.tm.rebaseObject(ttid, oid)
+        if request_time and SLOW_STORE is not None:
+            duration = time.time() - request_time
+            if duration > SLOW_STORE:
+                logging.info('RebaseObject delay: %.02fs', duration)
+        conn.answer(Packets.AnswerRebaseObject(conflict))
 
     def askTIDsFrom(self, conn, min_tid, max_tid, length, partition):
         conn.answer(Packets.AnswerTIDsFrom(self.app.dm.getReplicationTIDList(
@@ -159,25 +170,12 @@ class ClientOperationHandler(EventHandler):
             p = Packets.AnswerObjectUndoSerial(object_tid_dict)
         conn.answer(p)
 
-    def askHasLock(self, conn, ttid, oid):
-        locking_tid = self.app.tm.getLockingTID(oid)
-        logging.info('%r check lock of %r:%r', conn, dump(ttid), dump(oid))
-        if locking_tid is None:
-            state = LockState.NOT_LOCKED
-        elif locking_tid is ttid:
-            state = LockState.GRANTED
-        else:
-            state = LockState.GRANTED_TO_OTHER
-        conn.answer(Packets.AnswerHasLock(oid, state))
-
     def askObjectHistory(self, conn, oid, first, last):
         if first >= last:
             raise ProtocolError('invalid offsets')
         app = self.app
         if app.tm.loadLocked(oid):
-            # Delay the response.
-            app.queueEvent(self.askObjectHistory, conn, (oid, first, last))
-            return
+            raise DelayEvent
         history_list = app.dm.getObjectHistory(oid, first, last - first)
         if history_list is None:
             p = Errors.OidNotFound(dump(oid))
@@ -185,36 +183,34 @@ class ClientOperationHandler(EventHandler):
             p = Packets.AnswerObjectHistory(oid, history_list)
         conn.answer(p)
 
-    def askCheckCurrentSerial(self, conn, ttid, serial, oid):
+    def askCheckCurrentSerial(self, conn, ttid, oid, serial):
         self.app.tm.register(conn, ttid)
-        self._askCheckCurrentSerial(conn, ttid, serial, oid, time.time())
+        try:
+            self._askCheckCurrentSerial(conn, ttid, oid, serial, None)
+        except DelayEvent:
+            # locked by a previous transaction, retry later
+            self.app.tm.queueEvent(self._askCheckCurrentSerial,
+                conn, (ttid, oid, serial, time.time()))
 
-    def _askCheckCurrentSerial(self, conn, ttid, serial, oid, request_time):
+    def _askCheckCurrentSerial(self, conn, ttid, oid, serial, request_time):
         try:
-            self.app.tm.checkCurrentSerial(ttid, serial, oid)
+            self.app.tm.checkCurrentSerial(ttid, oid, serial)
         except ConflictError, err:
             # resolvable or not
-            conn.answer(Packets.AnswerCheckCurrentSerial(1, oid, err.tid))
-        except DelayedError:
-            # locked by a previous transaction, retry later
-            try:
-                self.app.queueEvent(self._askCheckCurrentSerial, conn, (ttid,
-                    serial, oid, request_time), key=(oid, ttid))
-            except AlreadyPendingError:
-                conn.answer(Errors.AlreadyPending(dump(oid)))
+            conn.answer(Packets.AnswerCheckCurrentSerial(err.tid))
         except NotRegisteredError:
             # transaction was aborted, cancel this event
             logging.info('Forget serial check of %s:%s by %s delayed by %s',
                 dump(oid), dump(serial), dump(ttid),
                 dump(self.app.tm.getLockingTID(oid)))
             # send an answer as the client side is waiting for it
-            conn.answer(Packets.AnswerCheckCurrentSerial(0, oid, serial))
+            conn.answer(Packets.AnswerCheckCurrentSerial(None))
         else:
-            if SLOW_STORE is not None:
+            if request_time and SLOW_STORE is not None:
                 duration = time.time() - request_time
                 if duration > SLOW_STORE:
                     logging.info('CheckCurrentSerial delay: %.02fs', duration)
-            conn.answer(Packets.AnswerCheckCurrentSerial(0, oid, serial))
+            conn.answer(Packets.AnswerCheckCurrentSerial(None))
 
 
 # like ClientOperationHandler but read-only & only for tid <= backup_tid
@@ -224,11 +220,12 @@ class ClientReadOnlyOperationHandler(ClientOperationHandler):
         conn.answer(Errors.ReadOnlyAccess(
             'read-only access because cluster is in backuping mode'))
 
-    abortTransaction        = _readOnly
     askStoreTransaction     = _readOnly
     askVoteTransaction      = _readOnly
     askStoreObject          = _readOnly
     askFinalTID             = _readOnly
+    askRebaseObject         = _readOnly
+    askRebaseTransaction    = _readOnly
     # takes write lock & is only used when going to commit
     askCheckCurrentSerial   = _readOnly
 

neo/storage/handlers/identification.py

@@ -27,6 +27,10 @@ class IdentificationHandler(EventHandler):
     def connectionLost(self, conn, new_state):
         logging.warning('A connection was lost during identification')
 
+    def getEventQueue(self):
+        # for requestIdentification
+        return self.app.nm
+
     def requestIdentification(self, conn, node_type, uuid, address, name,
                               id_timestamp):
         self.checkClusterName(name)
@@ -43,12 +47,6 @@ class IdentificationHandler(EventHandler):
             if uuid == app.uuid:
                 raise ProtocolError("uuid conflict or loopback connection")
             node = app.nm.getByUUID(uuid, id_timestamp)
-            if node is None:
-                # Do never create node automatically, or we could get id
-                # conflicts. We must only rely on the notifications from the
-                # master to recognize nodes. So this is not always an error:
-                # maybe there are incoming notifications.
-                raise NotReadyError('unknown node: retry later')
             if node.isBroken():
                 raise BrokenNodeDisallowedError
             # choose the handler according to the node type

neo/storage/handlers/master.py

@@ -31,8 +31,8 @@ class MasterOperationHandler(BaseMasterHandler):
             dm._setBackupTID(dm.getLastIDs()[0] or ZERO_TID)
             dm.commit()
 
-    def notifyTransactionFinished(self, conn, *args, **kw):
-        self.app.replicator.transactionFinished(*args, **kw)
+    def notifyTransactionFinished(self, conn, *args):
+        self.app.replicator.transactionFinished(*args)
 
     def notifyPartitionChanges(self, conn, ptid, cell_list):
         """This is very similar to Send Partition Table, except that
@@ -57,6 +57,10 @@ class MasterOperationHandler(BaseMasterHandler):
     def notifyUnlockInformation(self, conn, ttid):
         self.app.tm.unlock(ttid)
 
+    def abortTransaction(self, conn, ttid, _):
+        self.app.tm.abort(ttid)
+        self.app.replicator.transactionFinished(ttid)
+
     def askPack(self, conn, tid):
         app = self.app
         logging.info('Pack started, up to %s...', dump(tid))

neo/storage/handlers/storage.py

@@ -17,7 +17,7 @@
 import weakref
 from functools import wraps
 from neo.lib.connection import ConnectionClosed
-from neo.lib.handler import EventHandler
+from neo.lib.handler import DelayEvent, EventHandler
 from neo.lib.protocol import Errors, NodeStates, Packets, ProtocolError, \
     ZERO_HASH
 
@@ -143,12 +143,14 @@ class StorageOperationHandler(EventHandler):
     # Server (all methods must set connection as server so that it isn't closed
     #         if client tasks are finished)
 
+    def getEventQueue(self):
+        return self.app.tm
+
     @checkFeedingConnection(check=True)
     def askCheckTIDRange(self, conn, *args):
         app = self.app
         if app.tm.isLockedTid(args[3]): # max_tid
-            app.queueEvent(self.askCheckTIDRange, conn, args)
-            return
+            raise DelayEvent
         msg_id = conn.getPeerId()
         conn = weakref.proxy(conn)
         def check():
@@ -187,9 +189,7 @@ class StorageOperationHandler(EventHandler):
             #   NotifyTransactionFinished(M->S) + AskFetchTransactions(S->S)
             # is faster than
             #   NotifyUnlockInformation(M->S)
-            app.queueEvent(self.askFetchTransactions, conn,
-                (partition, length, min_tid, max_tid, tid_list))
-            return
+            raise DelayEvent
         msg_id = conn.getPeerId()
         conn = weakref.proxy(conn)
         peer_tid_set = set(tid_list)

neo/storage/replicator.py

@@ -29,7 +29,7 @@ partitions.
 
 2 parts, done sequentially:
 - Transaction (metadata) replication
-- Object (data) replication
+- Object (metadata+data) replication
 
 Both parts follow the same mechanism:
 - The range of data to replicate is split into chunks of FETCH_COUNT items
@@ -37,15 +37,52 @@ Both parts follow the same mechanism:
 - For every chunk, the requesting node sends to seeding node the list of items
   it already has.
 - Before answering, the seeding node sends 1 packet for every missing item.
+  For items that are already on the replicating node, there is no check that
+  values matches.
 - The seeding node finally answers with the list of items to delete (usually
   empty).
 
-Replication is partial, starting from the greatest stored tid in the partition:
-- For transactions, this tid is excluded from replication.
-- For objects, this tid is included unless the storage already knows it has
-  all oids for it.
-
-There is no check that item values on both nodes matches.
+Internal replication, which is similar to RAID1 (and as opposed to asynchronous
+replication to a backup cluster) requires extra care with respect to
+transactions. The transition of a cell from OUT_OF_DATE to UP_TO_DATE is done
+is several steps.
+
+A replicating node can not depend on other nodes to fetch the data
+recently/being committed because that can not be done atomically: it could miss
+writes between the processing of its request by a source node and the reception
+of the answer.
+
+Therefore, outdated cells are writable: a storage node asks the master for
+transactions being committed and then it is expected to fully receive from the
+client any transaction that is started after this answer.
+
+Which has in turn other consequences:
+- The client must not fail to write to a storage node after the above request
+  to the master: for this, the storage must have announced it is ready, and it
+  must delay identification of unknown clients (those for which it hasn't
+  received yet a notification from the master).
+- Writes must be accepted blindly (i.e. without taking a write-lock) when a
+  storage node lacks the data to check for conflicts. This is possible because
+  1 up-to-date cell (for each partition) is enough to do these checks.
+- Because the client can not reliably know if a storage node is expected to
+  receive a transaction in full, all writes must succeed.
+- Even if the replication is finished, we have to wait that we don't have any
+  lockless writes left before announcing to the master that we're up-to-date.
+
+To sum up:
+1. ask unfinished transactions -> (last_transaction, ttid_list)
+2. replicate to last_transaction
+3. wait for all ttid_list to be finished -> new last_transaction
+4. replicate to last_transaction
+5. no lockless write anymore, except to (oid, ttid) that were already
+   stored/checked without taking a lock
+6. wait for all transactions with lockless writes to be finished
+7. announce we're up-to-date
+
+For any failed write, the client marks the storage node as failed and stops
+writing to it for the transaction. Unless there's no failed write, vote ends
+with an extra request to the master: the transaction will only succeed if the
+failed nodes can be disconnected, forcing them to replicate the missing data.
 
 TODO: Packing and replication currently fail when they happen at the same time.
 """
@@ -85,11 +122,6 @@ class Replicator(object):
         if node is not None and node.isConnected(True):
             return node.getConnection()
 
-    # XXX: We can't replicate unfinished transactions but do we need such
-    #      complex code ? Backup mechanism does not rely on this: instead
-    #      the upstream storage delays the answer. Maybe we can do the same
-    #      for internal replication.
-
     def setUnfinishedTIDList(self, max_tid, ttid_list, offset_list):
         """This is a callback from MasterOperationHandler."""
         assert self.ttid_set.issubset(ttid_list), (self.ttid_set, ttid_list)
@@ -103,13 +135,18 @@ class Replicator(object):
             self.replicate_dict[offset] = max_tid
         self._nextPartition()
 
-    def transactionFinished(self, ttid, max_tid):
+    def transactionFinished(self, ttid, max_tid=None):
         """ Callback from MasterOperationHandler """
+        try:
             self.ttid_set.remove(ttid)
+        except KeyError:
+            assert max_tid is None, max_tid
+            return
         min_ttid = min(self.ttid_set) if self.ttid_set else INVALID_TID
         for offset, p in self.partition_dict.iteritems():
             if p.max_ttid and p.max_ttid < min_ttid:
                 p.max_ttid = None
+                if max_tid:
                     self.replicate_dict[offset] = max_tid
         self._nextPartition()
 
@@ -136,7 +173,7 @@ class Replicator(object):
         app = self.app
         pt = app.pt
         uuid = app.uuid
-        self.partition_dict = p = {}
+        self.partition_dict = {}
         self.replicate_dict = {}
         self.source_dict = {}
         self.ttid_set = set()
@@ -160,8 +197,7 @@ class Replicator(object):
                         p.next_trans = p.next_obj = next_tid
                         p.max_ttid = None
         if outdated_list:
-            self.app.master_conn.ask(Packets.AskUnfinishedTransactions(),
-                                     offset_list=outdated_list)
+            self.app.tm.replicating(outdated_list)
 
     def notifyPartitionChanges(self, cell_list):
         """This is a callback from MasterOperationHandler."""
@@ -190,8 +226,7 @@ class Replicator(object):
                     p.max_ttid = INVALID_TID
                     added_list.append(offset)
         if added_list:
-            self.app.master_conn.ask(Packets.AskUnfinishedTransactions(),
-                                     offset_list=added_list)
+            self.app.tm.replicating(added_list)
         if abort:
             self.abort()
 
@@ -325,9 +360,10 @@ class Replicator(object):
         p = self.partition_dict[offset]
         p.next_obj = add64(tid, 1)
         self.updateBackupTID()
-        if not p.max_ttid:
-            p = Packets.NotifyReplicationDone(offset, tid)
-            self.app.master_conn.notify(p)
+        if p.max_ttid:
+            logging.debug("unfinished transactions: %r", self.ttid_set)
+        else:
+            self.app.tm.replicated(offset, tid)
         logging.debug("partition %u replicated up to %s from %r",
                       offset, dump(tid), self.current_node)
         self.getCurrentConnection().setReconnectionNoDelay()

neo/tests/__init__.py

@@ -37,6 +37,7 @@ from time import time
 from struct import pack, unpack
 from unittest.case import _ExpectedFailure, _UnexpectedSuccess
 try:
+    from transaction.interfaces import IDataManager
     from ZODB.utils import newTid
 except ImportError:
     pass
@@ -378,6 +379,30 @@ class NeoUnitTestBase(NeoTestBase):
         return packet
 
 
+class TransactionalResource(object):
+
+    class _sortKey(object):
+
+        def __init__(self, last):
+            self._last = last
+
+        def __cmp__(self, other):
+            assert type(self) is not type(other), other
+            return 1 if self._last else -1
+
+    def __init__(self, txn, last, **kw):
+        self.sortKey = lambda: self._sortKey(last)
+        for k in kw:
+            assert callable(IDataManager.get(k)), k
+        self.__dict__.update(kw)
+        txn.get().join(self)
+
+    def __getattr__(self, attr):
+        if callable(IDataManager.get(attr)):
+            return lambda *_: None
+        return self.__getattribute__(attr)
+
+
 class Patch(object):
     """
     Patch attributes and revert later automatically.

neo/tests/client/testClientApp.py

@@ -43,9 +43,6 @@ def _ask(self, conn, packet, handler=None, **kw):
         handler.dispatch(conn, conn.fakeReceived())
     return self.getHandlerData()
 
-def failing_tryToResolveConflict(oid, conflict_serial, serial, data):
-    raise ConflictError
-
 class ClientApplicationTests(NeoUnitTestBase):
 
     def setUp(self):
@@ -73,7 +70,7 @@ class ClientApplicationTests(NeoUnitTestBase):
 
     def _begin(self, app, txn, tid):
         txn_context = app._txn_container.new(txn)
-        txn_context['ttid'] = tid
+        txn_context.ttid = tid
         return txn_context
 
     def getApp(self, master_nodes=None, name='test', **kw):
@@ -115,7 +112,7 @@ class ClientApplicationTests(NeoUnitTestBase):
         # connection to SN close
         self.assertFalse(oid in cache._oid_dict)
         conn = Mock({'getAddress': ('', 0)})
-        app.cp = Mock({'iterateForObject': [(Mock(), conn)]})
+        app.cp = Mock({'iterateForObject': (conn,)})
         def fakeReceived(packet):
             packet.setId(0)
             conn.fakeReceived = iter((packet,)).next
@@ -182,11 +179,8 @@ class ClientApplicationTests(NeoUnitTestBase):
         tid = self.makeTID()
         txn = self.makeTransactionObject()
         app.master_conn = Mock()
-        conn = Mock()
-        self.assertRaises(StorageTransactionError, app.undo, tid,
-            txn, failing_tryToResolveConflict)
+        self.assertRaises(StorageTransactionError, app.undo, tid, txn)
         # no packet sent
-        self.checkNoPacketSent(conn)
         self.checkNoPacketSent(app.master_conn)
 
     def test_connectToPrimaryNode(self):

neo/tests/functional/testClient.py

@@ -23,7 +23,6 @@ import socket
 from struct import pack
 from neo.lib.util import makeChecksum, u64
 from ZODB.FileStorage import FileStorage
-from ZODB.POSException import ConflictError
 from ZODB.tests.StorageTestBase import zodb_pickle
 from persistent import Persistent
 from . import NEOCluster, NEOFunctionalTest
@@ -41,25 +40,6 @@ class Tree(Persistent):
         self.right = Tree(depth)
         self.left = Tree(depth)
 
-
-# simple persistent object with conflict resolution
-class PCounter(Persistent):
-
-    _value = 0
-
-    def value(self):
-        return self._value
-
-    def inc(self):
-        self._value += 1
-
-
-class PCounterWithResolution(PCounter):
-
-    def _p_resolveConflict(self, old, saved, new):
-        new['_value'] = saved['_value'] + new['_value']
-        return new
-
 class PObject(Persistent):
     pass
 
@@ -93,29 +73,6 @@ class ClientTests(NEOFunctionalTest):
         conn = self.db.open(transaction_manager=txn)
         return (txn, conn)
 
-    def testConflictResolutionTriggered1(self):
-        """ Check that ConflictError is raised on write conflict """
-        # create the initial objects
-        self.__setup()
-        t, c = self.makeTransaction()
-        c.root()['without_resolution'] = PCounter()
-        t.commit()
-
-        # first with no conflict resolution
-        t1, c1 = self.makeTransaction()
-        t2, c2 = self.makeTransaction()
-        o1 = c1.root()['without_resolution']
-        o2 = c2.root()['without_resolution']
-        self.assertEqual(o1.value(), 0)
-        self.assertEqual(o2.value(), 0)
-        o1.inc()
-        o2.inc()
-        o2.inc()
-        t1.commit()
-        self.assertEqual(o1.value(), 1)
-        self.assertEqual(o2.value(), 2)
-        self.assertRaises(ConflictError, t2.commit)
-
     def testIsolationAtZopeLevel(self):
         """ Check transaction isolation within zope connection """
         self.__setup()
@@ -254,33 +211,6 @@ class ClientTests(NEOFunctionalTest):
         self.__checkTree(neo_conn.root()['trees'])
         self.assertEqual(dump, self.__dump(neo_db.storage))
 
-    def testLockTimeout(self):
-        """ Hold a lock on an object to block a second transaction """
-        def test():
-            self.neo = NEOCluster(['test_neo1'], replicas=0,
-                temp_dir=self.getTempDirectory())
-            self.neo.start()
-            # BUG: The following 2 lines creates 2 app, i.e. 2 TCP connections
-            #      to the storage, so there may be a race condition at network
-            #      level and 'st2.store' may be effective before 'st1.store'.
-            db1, conn1 = self.neo.getZODBConnection()
-            db2, conn2 = self.neo.getZODBConnection()
-            st1, st2 = conn1._storage, conn2._storage
-            t1, t2 = transaction.Transaction(), transaction.Transaction()
-            t1.user = t2.user = u'user'
-            t1.description = t2.description = u'desc'
-            oid = st1.new_oid()
-            rev = '\0' * 8
-            data = zodb_pickle(PObject())
-            st2.tpc_begin(t2)
-            st1.tpc_begin(t1)
-            st1.store(oid, rev, data, '', t1)
-            # this store will be delayed
-            st2.store(oid, rev, data, '', t2)
-            # the vote will timeout as t1 never release the lock
-            self.assertRaises(ConflictError, st2.tpc_vote, t2)
-        self.runWithTimeout(40, test)
-
     def testIPv6Client(self):
         """ Test the connectivity of an IPv6 connection for neo client """
 
@@ -297,51 +227,6 @@ class ClientTests(NEOFunctionalTest):
             db2, conn2 = self.neo.getZODBConnection()
         self.runWithTimeout(40, test)
 
-    def testDelayedLocksCancelled(self):
-        """
-            Hold a lock on an object, try to get another lock on the same
-            object to delay it. Then cancel the second transaction and check
-            that the lock is not hold when the first transaction ends
-        """
-        def test():
-            self.neo = NEOCluster(['test_neo1'], replicas=0,
-                temp_dir=self.getTempDirectory())
-            self.neo.start()
-            db1, conn1 = self.neo.getZODBConnection()
-            db2, conn2 = self.neo.getZODBConnection()
-            st1, st2 = conn1._storage, conn2._storage
-            t1, t2 = transaction.Transaction(), transaction.Transaction()
-            t1.user = t2.user = u'user'
-            t1.description = t2.description = u'desc'
-            oid = st1.new_oid()
-            rev = '\0' * 8
-            data = zodb_pickle(PObject())
-            st1.tpc_begin(t1)
-            st2.tpc_begin(t2)
-            # t1 own the lock
-            st1.store(oid, rev, data, '', t1)
-            # t2 store is delayed
-            st2.store(oid, rev, data, '', t2)
-            # cancel t2, should cancel the store too
-            st2.tpc_abort(t2)
-            # finish t1, should release the lock
-            st1.tpc_vote(t1)
-            st1.tpc_finish(t1)
-            db3, conn3 = self.neo.getZODBConnection()
-            st3 = conn3._storage
-            t3 = transaction.Transaction()
-            t3.user = u'user'
-            t3.description = u'desc'
-            st3.tpc_begin(t3)
-            # retrieve the last revision
-            data, serial = st3.load(oid)
-            # try to store again, should not be delayed
-            st3.store(oid, serial, data, '', t3)
-            # the vote should not timeout
-            st3.tpc_vote(t3)
-            st3.tpc_finish(t3)
-        self.runWithTimeout(10, test)
-
     def testGreaterOIDSaved(self):
         """
             Store an object with an OID greater than the last generated by the

neo/tests/master/testClientHandler.py

@@ -19,8 +19,8 @@ from ..mock import Mock
 from .. import NeoUnitTestBase
 from neo.lib.util import p64
 from neo.lib.protocol import NodeTypes, NodeStates, Packets
-from neo.master.handlers.client import ClientServiceHandler
 from neo.master.app import Application
+from neo.master.handlers.client import ClientServiceHandler
 
 class MasterClientHandlerTests(NeoUnitTestBase):
 
@@ -39,8 +39,6 @@ class MasterClientHandlerTests(NeoUnitTestBase):
         # define some variable to simulate client and storage node
         self.client_port = 11022
         self.storage_port = 10021
-        self.master_port = 10010
-        self.master_address = ('127.0.0.1', self.master_port)
         self.client_address = ('127.0.0.1', self.client_port)
         self.storage_address = ('127.0.0.1', self.storage_port)
         self.storage_uuid = self.getStorageUUID()
@@ -63,105 +61,6 @@ class MasterClientHandlerTests(NeoUnitTestBase):
         )
         return uuid
 
-    def checkAnswerBeginTransaction(self, conn):
-        return self.checkAnswerPacket(conn, Packets.AnswerBeginTransaction)
-
-    # Tests
-    def test_07_askBeginTransaction(self):
-        tid1 = self.getNextTID()
-        tid2 = self.getNextTID()
-        service = self.service
-        tm_org = self.app.tm
-        self.app.tm = tm = Mock({
-            'begin': '\x00\x00\x00\x00\x00\x00\x00\x01',
-        })
-        # client call it
-        client_uuid = self.identifyToMasterNode(node_type=NodeTypes.CLIENT, port=self.client_port)
-        client_node = self.app.nm.getByUUID(client_uuid)
-        conn = self.getFakeConnection(client_uuid, self.client_address)
-        service.askBeginTransaction(conn, None)
-        calls = tm.mockGetNamedCalls('begin')
-        self.assertEqual(len(calls), 1)
-        calls[0].checkArgs(client_node, None)
-        self.checkAnswerBeginTransaction(conn)
-        # Client asks for a TID
-        conn = self.getFakeConnection(client_uuid, self.client_address)
-        self.app.tm = tm_org
-        service.askBeginTransaction(conn, tid1)
-        calls = tm.mockGetNamedCalls('begin')
-        self.assertEqual(len(calls), 1)
-        calls[0].checkArgs(client_node, None)
-        packet = self.checkAnswerBeginTransaction(conn)
-        self.assertEqual(packet.decode(), (tid1, ))
-
-    def test_08_askNewOIDs(self):
-        service = self.service
-        oid1, oid2 = p64(1), p64(2)
-        self.app.tm.setLastOID(oid1)
-        # client call it
-        client_uuid = self.identifyToMasterNode(node_type=NodeTypes.CLIENT, port=self.client_port)
-        conn = self.getFakeConnection(client_uuid, self.client_address)
-        for node in self.app.nm.getStorageList():
-            conn = self.getFakeConnection(node.getUUID(), node.getAddress())
-            node.setConnection(conn)
-        service.askNewOIDs(conn, 1)
-        self.assertTrue(self.app.tm.getLastOID() > oid1)
-
-    def test_09_askFinishTransaction(self):
-        service = self.service
-        # do the right job
-        client_uuid = self.identifyToMasterNode(node_type=NodeTypes.CLIENT, port=self.client_port)
-        storage_uuid = self.storage_uuid
-        storage_conn = self.getFakeConnection(storage_uuid,
-            self.storage_address, is_server=True)
-        storage2_uuid = self.identifyToMasterNode(port=10022)
-        storage2_conn = self.getFakeConnection(storage2_uuid,
-            (self.storage_address[0], self.storage_address[1] + 1),
-            is_server=True)
-        self.app.setStorageReady(storage2_uuid)
-        conn = self.getFakeConnection(client_uuid, self.client_address)
-        self.app.pt = Mock({
-            'getPartition': 0,
-            'getCellList': [
-                Mock({'getUUID': storage_uuid}),
-                Mock({'getUUID': storage2_uuid}),
-            ],
-            'getPartitions': 2,
-        })
-        ttid = self.getNextTID()
-        service.askBeginTransaction(conn, ttid)
-        conn = self.getFakeConnection(client_uuid, self.client_address)
-        self.app.nm.getByUUID(storage_uuid).setConnection(storage_conn)
-        # No packet sent if storage node is not ready
-        self.assertFalse(self.app.isStorageReady(storage_uuid))
-        service.askFinishTransaction(conn, ttid, (), ())
-        self.checkNoPacketSent(storage_conn)
-        # ...but AskLockInformation is sent if it is ready
-        self.app.setStorageReady(storage_uuid)
-        self.assertTrue(self.app.isStorageReady(storage_uuid))
-        service.askFinishTransaction(conn, ttid, (), ())
-        self.checkAskPacket(storage_conn, Packets.AskLockInformation)
-        self.assertEqual(len(self.app.tm.registerForNotification(storage_uuid)), 1)
-        txn = self.app.tm[ttid]
-        pending_ttid = list(self.app.tm.registerForNotification(storage_uuid))[0]
-        self.assertEqual(ttid, pending_ttid)
-        self.assertEqual(len(txn.getOIDList()), 0)
-        self.assertEqual(len(txn.getUUIDList()), 1)
-
-    def test_connectionClosed(self):
-        # give a client uuid which have unfinished transactions
-        client_uuid = self.identifyToMasterNode(node_type=NodeTypes.CLIENT,
-                                                port = self.client_port)
-        conn = self.getFakeConnection(client_uuid, self.client_address)
-        self.app.listening_conn = object() # mark as running
-        lptid = self.app.pt.getID()
-        self.assertEqual(self.app.nm.getByUUID(client_uuid).getState(),
-                NodeStates.RUNNING)
-        self.service.connectionClosed(conn)
-        # node must be have been remove, and no more transaction must remains
-        self.assertEqual(self.app.nm.getByUUID(client_uuid), None)
-        self.assertEqual(lptid, self.app.pt.getID())
-
     def test_askPack(self):
         self.assertEqual(self.app.packing, None)
         self.app.nm.createClient()

neo/tests/master/testElectionHandler.py

@@ -19,9 +19,9 @@ from ..mock import Mock
 from neo.lib import protocol
 from .. import NeoUnitTestBase
 from neo.lib.protocol import NodeTypes, NodeStates, Packets
+from neo.master.app import Application
 from neo.master.handlers.election import ClientElectionHandler, \
         ServerElectionHandler
-from neo.master.app import Application
 from neo.lib.exception import ElectionFailure
 from neo.lib.connection import ClientConnection
 

neo/tests/master/testTransactions.py

@@ -24,66 +24,11 @@ from neo.master.transactions import TransactionManager
 
 class testTransactionManager(NeoUnitTestBase):
 
-    def makeOID(self, i):
-        return pack('!Q', i)
-
     def makeNode(self, node_type):
         uuid = self.getNewUUID(node_type)
         node = Mock({'getUUID': uuid, '__hash__': uuid, '__repr__': 'FakeNode'})
         return uuid, node
 
-    def test_storageLost(self):
-        client1 = Mock({'__hash__': 1})
-        client2 = Mock({'__hash__': 2})
-        client3 = Mock({'__hash__': 3})
-        storage_1_uuid = self.getStorageUUID()
-        storage_2_uuid = self.getStorageUUID()
-        oid_list = [self.makeOID(1), ]
-
-        tm = TransactionManager(None)
-        # Transaction 1: 2 storage nodes involved, one will die and the other
-        # already answered node lock
-        msg_id_1 = 1
-        ttid1 = tm.begin(client1)
-        tid1 = tm.prepare(ttid1, 1, oid_list,
-            [storage_1_uuid, storage_2_uuid], msg_id_1)
-        tm.lock(ttid1, storage_2_uuid)
-        t1 = tm[ttid1]
-        self.assertFalse(t1.locked())
-        # Storage 1 dies:
-        # t1 is over
-        self.assertTrue(t1.storageLost(storage_1_uuid))
-        self.assertEqual(t1.getUUIDList(), [storage_2_uuid])
-        del tm[ttid1]
-
-        # Transaction 2: 2 storage nodes involved, one will die
-        msg_id_2 = 2
-        ttid2 = tm.begin(client2)
-        tid2 = tm.prepare(ttid2, 1, oid_list,
-            [storage_1_uuid, storage_2_uuid], msg_id_2)
-        t2 = tm[ttid2]
-        self.assertFalse(t2.locked())
-        # Storage 1 dies:
-        # t2 still waits for storage 2
-        self.assertFalse(t2.storageLost(storage_1_uuid))
-        self.assertEqual(t2.getUUIDList(), [storage_2_uuid])
-        self.assertTrue(t2.lock(storage_2_uuid))
-        del tm[ttid2]
-
-        # Transaction 3: 1 storage node involved, which won't die
-        msg_id_3 = 3
-        ttid3 = tm.begin(client3)
-        tid3 = tm.prepare(ttid3, 1, oid_list, [storage_2_uuid, ],
-            msg_id_3)
-        t3 = tm[ttid3]
-        self.assertFalse(t3.locked())
-        # Storage 1 dies:
-        # t3 doesn't care
-        self.assertFalse(t3.storageLost(storage_1_uuid))
-        self.assertEqual(t3.getUUIDList(), [storage_2_uuid])
-        self.assertTrue(t3.lock(storage_2_uuid))
-        del tm[ttid3]
-
     def testTIDUtils(self):
         """
         Tests packTID/unpackTID/addTID.
@@ -110,53 +55,14 @@ class testTransactionManager(NeoUnitTestBase):
             unpackTID(addTID(packTID((2010, 11, 30, 23, 59), 2**32 - 1), 1)),
             ((2010, 12, 1, 0, 0), 0))
 
-    def testTransactionLock(self):
-        """
-        Transaction lock is present to ensure invalidation TIDs are sent in
-        strictly increasing order.
-        Note: this implementation might change later, for more parallelism.
-        """
-        client_uuid, client = self.makeNode(NodeTypes.CLIENT)
-        tm = TransactionManager(None)
-        # With a requested TID, lock spans from begin to remove
-        ttid1 = self.getNextTID()
-        ttid2 = self.getNextTID()
-        tid1 = tm.begin(client, ttid1)
-        self.assertEqual(tid1, ttid1)
-        del tm[ttid1]
-        # Without a requested TID, lock spans from prepare to remove only
-        ttid3 = tm.begin(client)
-        ttid4 = tm.begin(client) # Doesn't raise
-        node = Mock({'getUUID': client_uuid, '__hash__': 0})
-        tid4 = tm.prepare(ttid4, 1, [], [], 0)
-        del tm[ttid4]
-        tm.prepare(ttid3, 1, [], [], 0)
-
     def testClientDisconectsAfterBegin(self):
         client_uuid1, node1 = self.makeNode(NodeTypes.CLIENT)
         tm = TransactionManager(None)
         tid1 = self.getNextTID()
         tid2 = self.getNextTID()
-        tm.begin(node1, tid1)
+        tm.begin(node1, 0, tid1)
         tm.clientLost(node1)
         self.assertTrue(tid1 not in tm)
 
-    def testUnlockPending(self):
-        callback = Mock()
-        uuid1, node1 = self.makeNode(NodeTypes.CLIENT)
-        uuid2, node2 = self.makeNode(NodeTypes.CLIENT)
-        storage_uuid = self.getStorageUUID()
-        tm = TransactionManager(callback)
-        ttid1 = tm.begin(node1)
-        ttid2 = tm.begin(node2)
-        tid1 = tm.prepare(ttid1, 1, [], [storage_uuid], 0)
-        tid2 = tm.prepare(ttid2, 1, [], [storage_uuid], 0)
-        tm.lock(ttid2, storage_uuid)
-        # txn 2 is still blocked by txn 1
-        self.assertEqual(len(callback.getNamedCalls('__call__')), 0)
-        tm.lock(ttid1, storage_uuid)
-        # both transactions are unlocked when txn 1 is fully locked
-        self.assertEqual(len(callback.getNamedCalls('__call__')), 2)
-
 if __name__ == '__main__':
     unittest.main()

neo/tests/storage/testClientHandler.py

@@ -20,7 +20,7 @@ from .. import NeoUnitTestBase
 from neo.storage.app import Application
 from neo.storage.handlers.client import ClientOperationHandler
 from neo.lib.util import p64
-from neo.lib.protocol import INVALID_TID, Packets, LockState
+from neo.lib.protocol import INVALID_TID, Packets
 
 class StorageClientHandlerTests(NeoUnitTestBase):
 
@@ -100,24 +100,5 @@ class StorageClientHandlerTests(NeoUnitTestBase):
         self.operation.askObjectUndoSerial(conn, tid, ltid, undone_tid, oid_list)
         self.checkErrorPacket(conn)
 
-    def test_askHasLock(self):
-        tid_1 = self.getNextTID()
-        tid_2 = self.getNextTID()
-        oid = self.getNextTID()
-        def getLockingTID(oid):
-            return locking_tid
-        self.app.tm.getLockingTID = getLockingTID
-        for locking_tid, status in (
-                    (None, LockState.NOT_LOCKED),
-                    (tid_1, LockState.GRANTED),
-                    (tid_2, LockState.GRANTED_TO_OTHER),
-                ):
-            conn = self._getConnection()
-            self.operation.askHasLock(conn, tid_1, oid)
-            p_oid, p_status = self.checkAnswerPacket(conn,
-                Packets.AnswerHasLock).decode()
-            self.assertEqual(oid, p_oid)
-            self.assertEqual(status, p_status)
-
 if __name__ == "__main__":
     unittest.main()

neo/tests/storage/testMasterHandler.py

@@ -16,7 +16,6 @@
 
 import unittest
 from ..mock import Mock
-from collections import deque
 from .. import NeoUnitTestBase
 from neo.storage.app import Application
 from neo.storage.handlers.master import MasterOperationHandler
@@ -31,10 +30,6 @@ class StorageMasterHandlerTests(NeoUnitTestBase):
         # create an application object
         config = self.getStorageConfiguration(master_number=1)
         self.app = Application(config)
-        self.app.transaction_dict = {}
-        self.app.store_lock_dict = {}
-        self.app.load_lock_dict = {}
-        self.app.event_queue = deque()
         # handler
         self.operation = MasterOperationHandler(self.app)
         # set pmn

neo/tests/storage/testStorageApp.py

@@ -19,9 +19,7 @@ from ..mock import Mock
 from .. import NeoUnitTestBase
 from neo.storage.app import Application
 from neo.lib.protocol import CellStates
-from collections import deque
 from neo.lib.pt import PartitionTable
-from neo.storage.exception import AlreadyPendingError
 
 class StorageAppTests(NeoUnitTestBase):
 
@@ -31,8 +29,6 @@ class StorageAppTests(NeoUnitTestBase):
         # create an application object
         config = self.getStorageConfiguration(master_number=1)
         self.app = Application(config)
-        self.app.event_queue = deque()
-        self.app.event_queue_dict = {}
 
     def _tearDown(self, success):
         self.app.close()
@@ -121,26 +117,6 @@ class StorageAppTests(NeoUnitTestBase):
         self.assertTrue(cell_list[0].getUUID() in (master_uuid, storage_uuid))
         self.assertTrue(cell_list[1].getUUID() in (master_uuid, storage_uuid))
 
-    def test_02_queueEvent(self):
-        self.assertEqual(len(self.app.event_queue), 0)
-        msg_id = 1325136
-        event = Mock({'__repr__': 'event'})
-        conn = Mock({'__repr__': 'conn', 'getPeerId': msg_id})
-        key = 'foo'
-        self.app.queueEvent(event, conn, ("test", ), key=key)
-        self.assertEqual(len(self.app.event_queue), 1)
-        _key, _event, _msg_id, _conn, args = self.app.event_queue[0]
-        self.assertEqual(key, _key)
-        self.assertEqual(msg_id, _msg_id)
-        self.assertEqual(len(args), 1)
-        self.assertEqual(args[0], "test")
-        self.assertRaises(AlreadyPendingError, self.app.queueEvent, event,
-            conn, ("test2", ), key=key)
-        self.assertEqual(len(self.app.event_queue), 1)
-        self.app.queueEvent(event, conn, ("test3", ), key=key,
-            raise_on_duplicate=False)
-        self.assertEqual(len(self.app.event_queue), 2)
-
 if __name__ == '__main__':
     unittest.main()
 

neo/tests/storage/testTransactions.py

@@ -28,7 +28,7 @@ class TransactionManagerTests(NeoUnitTestBase):
         self.app = Mock()
         # no history
         self.app.dm = Mock({'getObjectHistory': []})
-        self.app.pt = Mock({'isAssigned': True})
+        self.app.pt = Mock({'isAssigned': True, 'getPartitions': 2})
         self.app.em = Mock({'setTimeout': None})
         self.manager = TransactionManager(self.app)
 

neo/tests/testDispatcher.py

-#
-# Copyright (C) 2009-2017  Nexedi SA
-#
-# This program is free software; you can redistribute it and/or
-# modify it under the terms of the GNU General Public License
-# as published by the Free Software Foundation; either version 2
-# of the License, or (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-from . import NeoTestBase
-from neo.lib.dispatcher import Dispatcher, ForgottenPacket
-from Queue import Queue
-import unittest
-
-class DispatcherTests(NeoTestBase):
-
-    def setUp(self):
-        NeoTestBase.setUp(self)
-        self.dispatcher = Dispatcher()
-
-    def testForget(self):
-        conn = object()
-        queue = Queue()
-        MARKER = object()
-        # Register an expectation
-        self.dispatcher.register(conn, 1, queue)
-        # ...and forget about it, returning registered queue
-        forgotten_queue = self.dispatcher.forget(conn, 1)
-        self.assertTrue(queue is forgotten_queue, (queue, forgotten_queue))
-        # A ForgottenPacket must have been put in the queue
-        queue_conn, packet, kw = queue.get(block=False)
-        self.assertTrue(isinstance(packet, ForgottenPacket), packet)
-        # ...with appropriate packet id
-        self.assertEqual(packet.getId(), 1)
-        # ...and appropriate connection
-        self.assertTrue(conn is queue_conn, (conn, queue_conn))
-        # If forgotten twice, it must raise a KeyError
-        self.assertRaises(KeyError, self.dispatcher.forget, conn, 1)
-        # Event arrives, return value must be True (it was expected)
-        self.assertTrue(self.dispatcher.dispatch(conn, 1, MARKER, {}))
-        # ...but must not have reached the queue
-        self.assertTrue(queue.empty())
-
-        # Register an expectation
-        self.dispatcher.register(conn, 1, queue)
-        # ...and forget about it
-        self.dispatcher.forget(conn, 1)
-        queue.get(block=False)
-        # No exception must happen if connection is lost.
-        self.dispatcher.unregister(conn)
-        # Forgotten message's queue must not have received a "None"
-        self.assertTrue(queue.empty())
-
-if __name__ == '__main__':
-    unittest.main()
-

neo/tests/testNodes.py

@@ -164,7 +164,7 @@ class NodeManagerTests(NeoUnitTestBase):
                 NodeStates.UNKNOWN, None),
         )
         # update manager content
-        manager.update(Mock(), node_list)
+        manager.update(Mock(), time(), node_list)
         # - the client gets down
         self.checkClients([])
         # - master change it's address

neo/tests/threaded/__init__.py

@@ -413,6 +413,9 @@ class ClientApplication(Node, neo.client.app.Application):
     def __init__(self, master_nodes, name, **kw):
         super(ClientApplication, self).__init__(master_nodes, name, **kw)
         self.poll_thread.node_name = name
+        # Smaller cache to speed up tests that checks behaviour when it's too
+        # small. See also NEOCluster.cache_size
+        self._cache._max_size //= 1024
 
     def _run(self):
         try:
@@ -433,6 +436,10 @@ class ClientApplication(Node, neo.client.app.Application):
                 conn = self.cp.getConnForNode(self.nm.getByUUID(peer.uuid))
             yield conn
 
+    def extraCellSortKey(self, key):
+        return Patch(self.cp, getCellSortKey=lambda orig, cell:
+            (orig(cell), key(cell)))
+
 class NeoCTL(neo.neoctl.app.NeoCTL):
 
     def __init__(self, *args, **kw):
@@ -541,7 +548,8 @@ class ConnectionFilter(object):
     def remove(self, *filters):
         with self.lock:
             for filter in filters:
-                del self.filter_dict[filter]
+                for p in self.filter_dict.pop(filter):
+                    p.revert()
             self._retry()
 
     def discard(self, *filters):
@@ -711,6 +719,10 @@ class NEOCluster(object):
     def primary_master(self):
         master, = [master for master in self.master_list if master.primary]
         return master
+
+    @property
+    def cache_size(self):
+        return self.client._cache._max_size
     ###
 
     def __enter__(self):
@@ -880,10 +892,6 @@ class NEOCluster(object):
         txn = transaction.TransactionManager()
         return txn, (self.db if db is None else db).open(txn)
 
-    def extraCellSortKey(self, key):
-        return Patch(self.client.cp, getCellSortKey=lambda orig, cell:
-            (orig(cell), key(cell)))
-
     def moduloTID(self, partition):
         """Force generation of TIDs that will be stored in given partition"""
         partition = p64(partition)
@@ -956,13 +964,12 @@ class NEOThreadedTest(NeoTestBase):
             return obj
         return unpickler
 
-    class newThread(threading.Thread):
+    class newPausedThread(threading.Thread):
 
         def __init__(self, func, *args, **kw):
             threading.Thread.__init__(self)
             self.__target = func, args, kw
             self.daemon = True
-            self.start()
 
         def run(self):
             try:
@@ -970,6 +977,8 @@ class NEOThreadedTest(NeoTestBase):
                 self.__exc_info = None
             except:
                 self.__exc_info = sys.exc_info()
+                if self.__exc_info[0] is NEOThreadedTest.failureException:
+                    traceback.print_exception(*self.__exc_info)
 
         def join(self, timeout=None):
             threading.Thread.join(self, timeout)
@@ -978,12 +987,64 @@ class NEOThreadedTest(NeoTestBase):
                 del self.__exc_info
                 raise etype, value, tb
 
+    class newThread(newPausedThread):
+
+        def __init__(self, *args, **kw):
+            NEOThreadedTest.newPausedThread.__init__(self, *args, **kw)
+            self.start()
+
     def commitWithStorageFailure(self, client, txn):
         with Patch(client, _getFinalTID=lambda *_: None):
             self.assertRaises(ConnectionClosed, txn.commit)
 
     def assertPartitionTable(self, cluster, stats):
-        self.assertEqual(stats, '|'.join(cluster.admin.pt.formatRows()))
+        pt = cluster.admin.pt
+        index = [x.uuid for x in cluster.storage_list].index
+        self.assertEqual(stats, '|'.join(pt._formatRows(sorted(
+            pt.count_dict, key=lambda x: index(x.getUUID())))))
+
+    @staticmethod
+    def noConnection(jar, storage):
+        return Patch(jar.db().storage.app.cp, getConnForNode=lambda orig, node:
+            None if node.getUUID() == storage.uuid else orig(node))
+
+    @staticmethod
+    def readCurrent(ob):
+        ob._p_activate()
+        ob._p_jar.readCurrent(ob)
+
+
+class ThreadId(list):
+
+    def __call__(self):
+        try:
+            return self.index(thread.get_ident())
+        except ValueError:
+            i = len(self)
+            self.append(thread.get_ident())
+            return i
+
+
+@apply
+class RandomConflictDict(dict):
+    # One must not depend on how Python iterates over dict keys, because this
+    # is implementation-defined behaviour. This patch makes sure of that when
+    # resolving conflicts.
+
+    def __new__(cls):
+        from neo.client.transactions import Transaction
+        def __init__(orig, self, *args):
+            orig(self, *args)
+            assert self.conflict_dict == {}
+            self.conflict_dict = dict.__new__(cls)
+        return Patch(Transaction, __init__=__init__)
+
+    def popitem(self):
+        try:
+            k = random.choice(list(self))
+        except IndexError:
+            raise KeyError
+        return k, self.pop(k)
 
 
 def predictable_random(seed=None):