1. 15 Oct, 2018 1 commit
  2. 09 Oct, 2018 2 commits
  3. 08 Oct, 2018 4 commits
  4. 02 Oct, 2018 3 commits
  5. 01 Oct, 2018 3 commits
    • Kirill Smelkov's avatar
      Merge branch 'master' into t · d3e124d1
      Kirill Smelkov authored
      * master:
        go/zodb: Don't truncate Tid time precision to 1µs
      d3e124d1
    • Kirill Smelkov's avatar
      go/zodb: Don't truncate Tid time precision to 1µs · 9112f21e
      Kirill Smelkov authored
      The format of tid assumes ~ ns precision, and it is only formatted to µs
      precision by default. So don't truncate TimeStamp value when computing
      it from Tid, and perform the µs-rounding only on formatting.
      
      The float numbers are not always exactly as in python. For example the
      following program
      
      	tidv = [
      	    0x0000000000000000,
      	    0x0285cbac258bf266,
      	    0x0285cbad27ae14e6,
      	    0x037969f722a53488,
      	    0x03b84285d71c57dd,
      	    0x03caa84275fc1166,
      	]
      
      	for tid in tidv:
      	    t = TimeStamp.TimeStamp(p64(tid))
      	    print '0x%016x %s %.9f\t%.9f' % (tid, t, t.timeTime(), t.second())
      
      prints:
      
      	0x0000000000000000 1900-01-01 00:00:00.000000 -2208988800.000000000     0.000000000
      	0x0285cbac258bf266 1979-01-03 21:00:08.800000 284245208.800000191       8.800000185
      	0x0285cbad27ae14e6 1979-01-03 21:01:09.300001 284245269.300001621       9.300001496	<-- ex here
      	0x037969f722a53488 2008-10-24 05:11:08.120000 1224825068.119999886      8.119999878
      	0x03b84285d71c57dd 2016-07-01 09:41:50.416574 1467366110.416574001      50.416573989
      	0x03caa84275fc1166 2018-10-01 16:34:27.652650 1538411667.652649879      27.652650112
      
      the difference is due to floating point operation ordering, because
      TimeStamp.timeTime() looses precision - e.g. for marked case:
      
      	In [8]: '%.10f' % (281566860.000000000 + 9.300001496)
      	Out[8]: '281566869.3000015020'
      
      We don't try to mimic float64 behaviour to Python exactly - because it is even
      different for PURE_PYTHON=y or C TimeStamp implementations. However we don't
      limit due to that our timestamp precision to only 1µs.
      
      In other words we keep on maintaining exact compatibility with Python on
      printing, but timestamp values itself are now ~ ns precision.
      9112f21e
    • Kirill Smelkov's avatar
      . · 74f0c47b
      Kirill Smelkov authored
      74f0c47b
  6. 30 Sep, 2018 3 commits
  7. 28 Sep, 2018 3 commits
    • Kirill Smelkov's avatar
      Merge branch 'master' into t · 754dc0e9
      Kirill Smelkov authored
      * master:
        go/zodb/fs1/index: Don't rely on []byte being pickled as string
      754dc0e9
    • Kirill Smelkov's avatar
      go/zodb/fs1/index: Don't rely on []byte being pickled as string · c72aaa0d
      Kirill Smelkov authored
      As https://github.com/kisielk/og-rek/pull/57 maybe shows []byte was
      pickling as string only unintentionally and that might change.
      
      We are already explicitly checking for string in corresponding index
      load place:
      
      	https://lab.nexedi.com/kirr/neo/blob/2dba8607/go/zodb/storage/fs1/index.go#L282
      
      so it is better we also explicitly save the bits as string.
      
      If we don't and https://github.com/kisielk/og-rek/pull/57 gets accepted,
      tests will fail:
      
      	--- FAIL: TestIndexSaveLoad (0.00s)
      	    index_test.go:176: index load: /tmp/t-index893650059/458967662/1.fs.index: pickle @6: invalid oidPrefix: type []uint8
      	Traceback (most recent call last):
      	  File "./py/indexcmp", line 41, in <module>
      	    main()
      	  File "./py/indexcmp", line 29, in main
      	    d2 = fsIndex.load(path2)
      	  File "/home/kirr/src/wendelin/z/ZODB/src/ZODB/fsIndex.py", line 138, in load
      	    data[ensure_bytes(k)] = fsBucket().fromString(ensure_bytes(v))
      	  File "/home/kirr/src/wendelin/z/ZODB/src/ZODB/fsIndex.py", line 71, in ensure_bytes
      	    return s.encode('ascii') if not isinstance(s, bytes) else s
      	AttributeError: 'bytearray' object has no attribute 'encode'
      	--- FAIL: TestIndexSaveToPy (0.04s)
      	    index_test.go:218: zodb/py read/compare index: exit status 1
      c72aaa0d
    • Kirill Smelkov's avatar
      . · de2f2c3c
      Kirill Smelkov authored
      de2f2c3c
  8. 04 Sep, 2018 2 commits
  9. 03 Sep, 2018 3 commits
  10. 31 Aug, 2018 1 commit
  11. 10 Aug, 2018 5 commits
  12. 09 Aug, 2018 10 commits
    • Kirill Smelkov's avatar
      Merge branch 'master' into t · cabc0f17
      Kirill Smelkov authored
      * master:
        go/zodb/btree: New package to work with ZODB BTrees (draft)
        go/zodb: DB - application-level handle to database (very draft)
        go/zodb: Connection: Allow applications to tune live-cache eviction policy
        go/zodb: Implement Connection
        go/zodb/internal/weak: New package to handle weak references
        go/zodb: PyStateful persistency support
        go/zodb: pydata: Factor out class extraction logic into xpyclass
        go/zodb: Persistent - the base type to implement IPersistent objects
        go/zodb: IPersistent + Connection stub
        go/zodb: pkgdoc: Add section overviewing storage drivers
        go/zodb: pkgdoc: Put zodbtools reference into "Miscellaneous" section
        go/zodb: pkgdoc: "Operations" -> "Storage layer"
        go/zodb: pkgdoc: Stress that objects can reference each other in the database
        go/zodb: Pkgdoc cosmetics
        go/zodb: Provide invalid Oid value
        go/zodb: OpenOptions: Document that NoCache disables prefetch
        go/transaction: New package to deal with transactions (very draft)
      cabc0f17
    • Kirill Smelkov's avatar
      . · c38f0493
      Kirill Smelkov authored
      c38f0493
    • Kirill Smelkov's avatar
      . · b4fe3075
      Kirill Smelkov authored
      b4fe3075
    • Kirill Smelkov's avatar
      go/zodb/btree: New package to work with ZODB BTrees (draft) · 2dba8607
      Kirill Smelkov authored
      Provide minimal support for BTrees.LOBTree Get for now.
      2dba8607
    • Kirill Smelkov's avatar
      go/zodb: DB - application-level handle to database (very draft) · 533f0c73
      Kirill Smelkov authored
      DB represents a handle to database at application level and contains pool
      of connections. DB.Open opens database connection. The connection will be
      automatically put back into DB pool for future reuse after corresponding
      transaction is complete. DB thus provides service to maintain live objects
      cache and reuse live objects from transaction to transaction.
      
      Note that it is possible to have several DB handles to the same database.
      This might be useful if application accesses distinctly different sets of
      objects in different transactions and knows beforehand which set it will be
      next time. Then, to avoid huge cache misses, it makes sense to keep DB
      handles opened for every possible case of application access.
      
      TODO handle invalidations.
      533f0c73
    • Kirill Smelkov's avatar
      go/zodb: Connection: Allow applications to tune live-cache eviction policy · c67ff9ea
      Kirill Smelkov authored
      For example Wendelin.core wcfs will need to keep some types of objects
      (e.g. BigFile index) always in RAM for efficiency.
      
      Provide corresponding interface that application could use to install
      such live-cache eviction decision-making tuning.
      c67ff9ea
    • Kirill Smelkov's avatar
      go/zodb: Implement Connection · fb343a6f
      Kirill Smelkov authored
      Connection represents an application-level view of a ZODB database.
      It has groups of in-RAM application-level objects associated with it.
      The objects are isolated from both changes in further database
      transactions and from changes to in-RAM objects in other connections.
      
      Connection, as objects group manager, is responsible for handling
      object -> object database references. For this to work it keeps
      
      	{} oid -> obj
      
      dict and uses it to find already loaded object when another object
      persistently references particular oid. Since it related pydata handling
      of persistent references is correspondingly implemented in this patch.
      
      The dict must keep weak references on objects. The following text
      explains the rationale:
      
      	if Connection keeps strong link to obj, just
      	obj.PDeactivate will not fully release obj if there are no
      	references to it from other objects:
      
      	     - deactivate will release obj state (ok)
      	     - but there will be still reference from connection `oid -> obj` map to this object,
      	       which means the object won't be garbage-collected.
      
      	-> we can solve it by using "weak" pointers in the map.
      
      	NOTE we cannot use regular map and arbitrarily manually "gc" entries
      	there periodically: since for an obj we don't know whether other
      	objects are referencing it, we can't just remove obj's oid from
      	the map - if we do so and there are other live objects that
      	reference obj, user code can still reach obj via those
      	references. On the other hand, if another, not yet loaded, object
      	also references obj and gets loaded, traversing reference from
      	that loaded object will load second copy of obj, thus breaking 1
      	object in db <-> 1 live object invariant:
      
      	     A  →  B  →  C
      	     ↓           |
      	     D <--------- - - -> D2 (wrong)
      
      	- A activate
      	- D activate
      	- B activate
      	- D gc, A still keeps link on D
      	- C activate -> it needs to get to D, but D was removed from objtab
      	  -> new D2 is wrongly created
      
      	that's why we have to depend on Go's GC to know whether there are
      	still live references left or not. And that in turn means finalizers
      	and thus weak references.
      
      	some link on the subject:
      	https://groups.google.com/forum/#!topic/golang-nuts/PYWxjT2v6ps
      fb343a6f
    • Kirill Smelkov's avatar
      go/zodb/internal/weak: New package to handle weak references · 79e28f3c
      Kirill Smelkov authored
      We will need weak references to handle {} oid -> obj inside zodb.Connection .
      
      In Go world they often say that weak references are not needed at all.
      Please see however the next patch for detailed rationale for why weak
      references (finalizers and cooperation from Go's GC in other words) are
      _required_ in that case.
      79e28f3c
    • Kirill Smelkov's avatar
      go/zodb: PyStateful persistency support · 532d014f
      Kirill Smelkov authored
      As promised in 354e0e51 (go/zodb: Persistent - the base type to
      implement IPersistent objects) add support to persistency machinery to
      set object state from python pickles serialized by ZODB/py.
      
      Persistent references are not yet handled.
      
      As promised add some very minimal persistent tests.
      532d014f
    • Kirill Smelkov's avatar
      go/zodb: pydata: Factor out class extraction logic into xpyclass · abc11031
      Kirill Smelkov authored
      Currently we handle many ways ZODB could serialize a Python class in
      PyData.ClassName. Since we'll be using this functionality in other
      places soon - extract it into dedicated function.
      
      Since will be also frequently using
      
      	class.__module__ + "." + class.__name__
      
      don't inline it in ClassName and instead put it into pyclassPath() right
      away.
      abc11031