RE: [ZODB-Dev] ZEO and setting instance variables in __getstate__
[Syver Enstad] >>> I have recently upgraded from ZODB 3.2 to 3.5.1. After doing this I >>> notice that ZEO throws exceptions on commiting a transaction for >>> certain types of Persistent classes. ... [Tim Peters] >> I was able to create a small self-contained test case from this >> description, and opened a Collector issue containing it: >> >> http://www.zope.org/Collectors/Zope3-dev/526 >> >> As it says, I don't know whether it "should work", but offhand don't see >> why not. As is, creating new state inside __getstate__ is confusing the >> heck out of ZEO's MVCC cache "for some reason". [Syver Enstad] > I noticed that the collector issue source file has a comment that this is > experienced on windows. My testing has been done on Linux Ubuntu Breezy > Badger and I get the same error, (cur_tid < tid) fails there too. The comment says specifically that cur_tid == tid on Windows, not just that cur_tid < tid fails. While they're probably equal on your box too, timing functions on Windows have such radically different pragmatics that I'm not assuming that. If they are equal on your box, please add a comment to the Collector issue saying so (comments on zodb-dev will soon be forgotten). ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] ZEO and setting instance variables in __getstate__
Tim Peters wrote: [Syver Enstad] I have recently upgraded from ZODB 3.2 to 3.5.1. After doing this I notice that ZEO throws exceptions on commiting a transaction for certain types of Persistent classes. ... I was able to create a small self-contained test case from this description, and opened a Collector issue containing it: http://www.zope.org/Collectors/Zope3-dev/526 As it says, I don't know whether it "should work", but offhand don't see why not. As is, creating new state inside __getstate__ is confusing the heck out of ZEO's MVCC cache "for some reason". I noticed that the collector issue source file has a comment that this is experienced on windows. My testing has been done on Linux Ubuntu Breezy Badger and I get the same error, (cur_tid < tid) fails there too. ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
RE: [ZODB-Dev] ZEO and setting instance variables in __getstate__
[Syver Enstad] > I have recently upgraded from ZODB 3.2 to 3.5.1. After doing this I > notice that ZEO throws exceptions on commiting a transaction for certain > types of Persistent classes. > ... I was able to create a small self-contained test case from this description, and opened a Collector issue containing it: http://www.zope.org/Collectors/Zope3-dev/526 As it says, I don't know whether it "should work", but offhand don't see why not. As is, creating new state inside __getstate__ is confusing the heck out of ZEO's MVCC cache "for some reason". ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
[ZODB-Dev] ZEO and setting instance variables in __getstate__
I have recently upgraded from ZODB 3.2 to 3.5.1. After doing this I notice that ZEO throws exceptions on commiting a transaction for certain types of Persistent classes. Here is the traceback. File "/usr/lib/python2.4/site-packages/transaction/_transaction.py", line 389, in commit self._saveCommitishError() # This raises! File "/usr/lib/python2.4/site-packages/transaction/_transaction.py", line 387, in commit self._commitResources() File "/usr/lib/python2.4/site-packages/transaction/_transaction.py", line 440, in _commitResources rm.tpc_finish(self) File "/usr/lib/python2.4/site-packages/ZODB/Connection.py", line 679, in tpc_finish self._storage.tpc_finish(transaction, callback) File "/usr/lib/python2.4/site-packages/ZEO/ClientStorage.py", line 974, in tpc_finish self._update_cache(tid) File "/usr/lib/python2.4/site-packages/ZEO/ClientStorage.py", line 999, in _update_cache self._cache.invalidate(oid, version, tid) File "/usr/lib/python2.4/site-packages/ZEO/cache.py", line 367, in invalidate assert tid is not None and cur_tid < tid AssertionError I narrowed it down to the problem occuring when I set instance variables in __getstate__ (called on commit) on a newly created persistent instance. This only happens when I am using ZEO (ClientStorage) and not when using ZODB (FileStorage). The reason I have chosen to override __getstate__ is to update the Persistent instance with the current username (which I store on the transaction when I open the connection) and a timestamp so that the instance knows when it was modified last and which user did it. The new beforeCommitHook seems to be suited for this kind of work, but it doesn't give access to the changed objects in the transaction. ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
