some more findings:

1. The conflict error really happens on the Portalcatalog
2. It is a BTreesConflictError: BTrees conflict error at -1/47/47: Conflicting inserts which disguised as ConflictError, through the various try: excepts:

3. It happens on DateIndexes like "created" and "modified".

4. I put for a test:
        try:
            resolved = resolve(old, committed, newstate)
        except:
            return "invalidated"

into tryToResolveConflict

and into the store-method of FileStorage:

if serial != cached_tid:
     rdata = self.tryToResolveConflict(oid, cached_tid,serial, data)
     if rdata is None:
raise POSException.ConflictError(oid=oid, serials=(cached_tid, serial), data=data)
         elif rdata == "invalidated":  #new for test
              old = False              #
              pass                     #

With these hacks I get rid of the conflictErrors. But when I delete the created Items I get: 2007-06-01 13:20:33 ERROR Zope.UnIndex DateIndex: unindex_object tried to retrieve set 1075379718 from index created but couldn't. This should not happen. 2007-06-01 13:20:33 ERROR Zope.UnIndex DateIndex: unindex_object tried to retrieve set 1075379838 from index Date but couldn't. This should not happen. 2007-06-01 13:20:33 ERROR Zope.UnIndex DateIndex: unindex_object tried to retrieve set 1075379719 from index modified but couldn't. This should not happen.

So obviously I just fix the symptom with this hack.
I think the real cause:

lies in these lines:

            if old:
                cached_tid = self._get_cached_tid(oid)
                if cached_tid is None:
                    h = self._read_data_header(old, oid)
                    if h.version:
                        if h.version != version:
                            raise VersionLockError(oid, h.version)
                        pnv = h.pnv
                    cached_tid = h.tid

                if serial != cached_tid:
rdata = self.tryToResolveConflict(oid, cached_tid,serial, data)

Which is also supported by the fact, that on our live system
which is running on 4 zeo-clients we get this traceback:


2007-06-01T12:38:59 ERROR Zope.SiteErrorLog http://uniben.waeup.org/campus/students/F541700/study_course/create_level
Traceback (innermost last):
  Module Zope2.App.startup, line 173, in zpublisher_exception_hook
  Module ZPublisher.Publish, line 121, in publish
  Module Zope2.App.startup, line 240, in commit
  Module transaction._manager, line 96, in commit
  Module Products.CPSCompat.PatchZODBTransaction, line 175, in commit
  Module transaction._transaction, line 436, in _commitResources
  Module ZODB.Connection, line 665, in tpc_vote
  Module ZEO.ClientStorage, line 893, in tpc_vote
  Module ZEO.ClientStorage, line 877, in _check_serials
ConflictError: database conflict error (oid 0x8fe833, class BTrees._IOBTree.IOBucket, serial this txn started with 0x036e0418ddcccf55 2007-06-01 11:36:51.984384, serial currently committed 0x036e041a3a33e311 2007-06-01 11:38:13.641254)


Any suggestion for a temporary fix would be very welcome, since we get about 6000 conflict errors per day now about 15 % unresolved, and they are really killing our portal.

--
Gruß Joachim

_______________________________________________
Zope-Dev maillist  -  Zope-Dev@zope.org
http://mail.zope.org/mailman/listinfo/zope-dev
**  No cross posts or HTML encoding!  **
(Related lists - http://mail.zope.org/mailman/listinfo/zope-announce
http://mail.zope.org/mailman/listinfo/zope )

Reply via email to