Dirk Datzert wrote:
Hi Zope developers,
I read that Zope 2.6.1 has a deadlock patch integrated.
- Deadlock prevention code added.
It was possible for earlier versions of ZODB to deadlock when using multiple storages. If multiple transactions committed concurrently and both transactions involved two or more shared storages, deadlock was possible. This problem has been fixed by introducing a sortKey() method to the transaction and storage APIs that is used to define an ordering on transaction participants. This solution will prevent deadlocks provided that all transaction participants that use locks define a valid sortKey() method. A warning is raised if a participant does not define sortKey(). For backwards compatibility, BaseStorage provides a sortKey() that uses __name__.
Can I find anywhere (maybe CVS) this patch ? I want to look if I can backport this to Zope 2.3.3, since we detected such deadlocks on our server.
The change was too extensive to call it a patch. It was almost a rewrite. If you want to dig through the repository, look for all changes made to ZODB and ZEO between about October 31, 2002 and January 3, 2003. I imagine it would be less work to upgrade to a more recent version of Zope. Shane