Blame view

CHANGES 5.96 KB
Julien Muchembled committed
1 2 3
Change History
==============

Julien Muchembled committed
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
1.3 (2015-01-13)
----------------

- Version 1.2 added a new 'Importer' storage backend but it had 2 bugs.

  - An interrupted migration could not be resumed.
  - Merging several ZODB only worked if NEO could import all classes used by
    the application. This has been fixed by repickling without loading any
    object.

- Logging has been improved for a better integration with the environment:

  - RTMIN+1 signal was changed to reopen logs. RTMIN+1 & RTMIN+2 signals, which
    were previously used for debugging, have been remapped to RTMIN+2 & RTMIN+3
  - In Zope, client registers automatically for log rotation (USR2).
  - NEO logs are SQLite DB that are not open anymore with a persistent journal,
    because this is incompatible with the rename+reopen way to rotate logs,
    and we want to support logrotate.
  - 'neolog' can now open gzip/bz2 compressed logs transparently.
  - 'neolog' does not spam the console anymore when piped to a process that
    exits prematurely.

- MySQL backend has been updated to work with recent MariaDB (>=10).
- 2 'neomaster' command-line options were added to set upstream cluster/masters.

Julien Muchembled committed
29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
1.2 (2014-07-30)
----------------

The most important changes in this version are the work about conversion of
databases from/to NEO:

- A new 'Importer' storage backend has been implemented and this is now the
  recommended way to migrate existing Zope databases. See 'importer.conf'
  example file for more information.
- 'neomigrate' command refused to run since version 1.0
- Exported data serials by NEO iterator were wrong. There are still differences
  with FileStorage:

  - NEO always resolves to original serial, to avoid any indirection
    (which slightly speeds up undo at the expense of a more complex pack code)
  - NEO does not make any difference between object deletion and creation undone
    (data serial always null in storage)

  Apart from that, conversion of database back from NEO should be fixed.

Other changes are:

- A warning was added in 'neo.conf' about a possible misuse of replicas.
- Compatibility with Python 2.6 has been dropped.
- Support for recent version of SQlite has been added.
- A memory leak has been fixed in replication.
- MySQL backend now fails instead of silently reconnecting if there is any
  pending change, which could cause data loss.
- Optimization and minor bugfixes.

Julien Muchembled committed
59 60 61 62 63 64 65 66 67 68 69 70
1.1 (2014-01-07)
----------------

- Client failed at reconnecting properly to master. It could kill the master
  (during tpc_finish!) or end up with invalid caches (i.e. possible data
  corruption). Now, connection to master is even optional between
  transaction.begin() and tpc_begin, as long as partition table contains
  up-to-date data.
- Compatibility with ZODB 3.9 has been dropped. Only 3.10.x branch is supported.
- checkCurrentSerialInTransaction was not working.
- Optimization and minor bugfixes.

Julien Muchembled committed
71
1.0 (2012-08-28)
Julien Muchembled committed
72 73
----------------

Julien Muchembled committed
74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92
This version mainly comes with stabilized SQL tables format and efficient backup
feature, relying on replication, which has been fully reimplemented:

- It is now incremental, instead of being done on whole partitions.
  Schema of MySQL tables have been changed in order to optimize storage layout,
  for good partial replication performance.
- It runs at lowest priority not to degrade performance for client nodes.
- A cluster in the new BACKINGUP state is a client to a normal cluster and all
  its storage nodes are notified of invalidations and replicate from upstream
  nodes.

Other changes are:

- Compatibility with Python < 2.6 and ZODB < 3.9 has been dropped.
- Cluster is now automatically started when all storage nodes of UP_TO_DATE
  cells are available, similarly to ``mdadm assemble --no-degraded`` behaviour.
- NEO learned to check replicas, to detect data corruption or bugs during
  replication. When done on a backup cluster, upstream data is used as
  reference. This is still limited to data indexes (tid & oid/serial).
Julien Muchembled committed
93 94 95 96
- NEO logs now are SQLite DB that always contain all debugging information
  including exchanged packets. Records are first kept in RAM, at most 16 MB by
  default, and there are flushed to disk only upon RTMIN signal or any important
  record. A 'neolog' script has been written to help reading such DB.
Julien Muchembled committed
97 98 99 100
- Master addresses must be separated by spaces. '/' can't be used anymore.
- Adding and removing master nodes is now easier: unknown incoming master nodes
  are now accepted instead of rejected, and nodes can be given a path to a file
  that maintains a list of known master nodes.
Julien Muchembled committed
101 102
- Node UUIDs have been shortened from 16 to 4 bytes, for better performance and
  easier debugging.
Julien Muchembled committed
103 104

Also contains code clean-ups and bugfixes.
Julien Muchembled committed
105

Julien Muchembled committed
106
0.10.1 (2012-03-13)
Julien Muchembled committed
107 108 109 110 111
-------------------

- Client didn't limit its memory usage when committing big transactions.
- Master failed to disconnect clients when cluster leaves RUNNING state.

Julien Muchembled committed
112
0.10 (2011-10-17)
Julien Muchembled committed
113 114
-----------------

Julien Muchembled committed
115 116
- Storage was unable or slow to process large-sized transactions.
  This required to change protocol and MySQL tables format.
Julien Muchembled committed
117 118 119
- NEO learned to store empty values (although it's useless when managed by
  a ZODB Connection).

Julien Muchembled committed
120
0.9.2 (2011-10-17)
Julien Muchembled committed
121 122
------------------

Julien Muchembled committed
123 124
- storage: a specific socket can be given to MySQL backend
- storage: a ConflictError could happen when client is much faster than master
Julien Muchembled committed
125
- 'verbose' command line option of 'neomigrate' did not work
Julien Muchembled committed
126
- client: ZODB monkey-patch randomly raised a NameError
Julien Muchembled committed
127

Julien Muchembled committed
128
0.9.1 (2011-09-24)
Julien Muchembled committed
129 130 131 132 133 134 135 136
------------------

- client: method to retrieve history of persistent objects was incompatible
  with recent ZODB and needlessly asked all storages systematically.
- neoctl: 'print node' command (to get list of all nodes) raised an
  AssertionError.
- 'neomigrate' raised a TypeError when converting NEO DB back to FileStorage.

Julien Muchembled committed
137 138 139 140 141 142 143 144 145 146 147
0.9 (2011-09-12)
----------------

Initial release.

NEO is considered stable enough to replace existing ZEO setups, except that:

- there's no backup mechanism (aka efficient snapshoting): there's only
  replication and underlying MySQL tools

- MySQL tables format may change in the future