This is a topic that comes up occasionally, but since the symptom seems to be rare and hard to provoke, it never gets resolved. Well it's biting me again and I'm determined to fix it, but would like some input from the list. Related collector issues: http://www.zope.org/Collectors/Zope/300 http://www.zope.org/Collectors/Zope/1201 The issue: On rare occasions I have seen ConflictErrors raised during product installation. Today, I can finally provoke them at will with a pretty minimal setup. The setup: Zope 2.7.3, using ZEO, with DirectoryStorage on the ZEO server. Hardware: dual-processor PIII 800, some kinda scsi disk, ext3, some old redhat flavor of linux. To provoke it I need merely do ./bin/zopectl run foo.py ... where foo.py is empty. Products/ now contains only one dummy product, which I've named Conflictor, which contains only an empty __init__.py. I get a ConflictError during registration of Conflictor. Interestingly I can only provoke this ConflictError in this particular INSTANCE_HOME. I have several other instances and am not seeing the symptom there. I started trivially hacking OFS/Application.py to add some debugging output (a diff against 2.7.3 is attached), and here's what I get: [pwinkler@dev-zope-knox01 PaulMiniInstanceHome]$ ls Products/ [pwinkler@dev-zope-knox01 PaulMiniInstanceHome]$ mkdir Products/Conflicter [pwinkler@dev-zope-knox01 PaulMiniInstanceHome]$ touch Products/Conflicter/__in it__.py [pwinkler@dev-zope-knox01 PaulMiniInstanceHome]$ touch foo.py [pwinkler@dev-zope-knox01 PaulMiniInstanceHome]$ ./bin/zopectl run foo.py installing product PluginIndexes...OK! installing product Conflicter... BZZT Traceback (most recent call last): File "<string>", line 1, in ? File "/usr/local/lib/python2.3/site-packages/PIL/__init__.py", line 51, in app File "/usr/local/lib/python2.3/site-packages/PIL/__init__.py", line 47, in startup File "/zope/Zope-2.7.3-SoftwareHome/lib/python/Zope/App/startup.py", line 96, in startup File "/zope/ZopeSoftwareHome/lib/python/OFS/Application.py", line 279, in init ialize initializer.initialize() File "/zope/ZopeSoftwareHome/lib/python/OFS/Application.py", line 306, in init ialize self.install_products() File "/zope/ZopeSoftwareHome/lib/python/OFS/Application.py", line 561, in inst all_products return install_products(app) File "/zope/ZopeSoftwareHome/lib/python/OFS/Application.py", line 597, in inst all_products folder_permissions, raise_exc=debug_mode) File "/zope/ZopeSoftwareHome/lib/python/OFS/Application.py", line 803, in inst all_product get_transaction().commit() File "/zope/Zope-2.7.3-SoftwareHome/lib/python/ZODB/Transaction.py", line 252, in commit File "/zope/Zope-2.7.3-SoftwareHome/lib/python/ZODB/Connection.py", line 738, in tpc_vote File "/zope/Zope-2.7.3-SoftwareHome/lib/python/ZEO/ClientStorage.py", line 841 , in tpc_vote File "/zope/Zope-2.7.3-SoftwareHome/lib/python/ZEO/ClientStorage.py", line 825 , in _check_serials ZODB.POSException.ConflictError: database conflict error (serial this txn starte d with 0x035b25f36751f988 2005-02-10 18:59:24.215675, serial currently committed 0x035b743c6d186822 2005-02-24 17:00:25.569220) I guess what I'm asking, before I hack more on OFS/Application.py, is this: * any ideas re. what on earth could be causing this ConflictError? the product doesn't DO anything fer chrissakes. (Maybe registration is finishing too fast??) * Is the PIL stuff in the traceback a red herring or what? -- Paul Winkler http://www.slinkp.com