[Zope] Zope 2.8 and conflict errors

[Chris McDonough]

I've lost context here... is this good or bad? ;-)

On Wed, 2005-08-03 at 16:32 +0200, Maciej Wisniowski wrote:
> > It might. ZEO adds network overhead to ZODB transactions,
> > which generally increases the likelihood of conflict errors.
> 
> I've created ZEO and executed the same test 
> with my application.
> 
> Tests were done with SQLRelay backend (DCOracle2 is 
> running now ;))
> 
> I have tested this with 50, 55, 60 and 70 users.
> with 50 users: no 'HTTP/1.1 500' errors
> with 55 users: no 'HTTP/1.1 500' errors
> with 60 users: no 'HTTP/1.1 500' 1 error for 1800 urls requested
> with 65 users: no 'HTTP/1.1 500' 4 errors for 1950 urls requested
> 
> All errors are with OOBTree and as I can see 
> with tempstorage.TemporaryStorage. They look like:
> 
> <li>  Module ZPublisher.Publish, line 187, in publish_module_standard</li>
> <li>  Module ZPublisher.Publish, line 161, in publish</li>
> <li>  Module ZPublisher.Publish, line 161, in publish</li>
> <li>  Module ZPublisher.Publish, line 161, in publish</li>
> <li>  Module ZPublisher.Publish, line 151, in publish</li>
> <li>  Module Zope2.App.startup, line 158, in zpublisher_exception_hook</li>
> <li>  Module ZPublisher.Publish, line 119, in publish</li>
> <li>  Module Zope2.App.startup, line 215, in commit</li>
> <li>  Module transaction._manager, line 84, in commit</li>
> <li>  Module transaction._transaction, line 381, in commit</li>
> <li>  Module transaction._transaction, line 379, in commit</li>
> <li>  Module transaction._transaction, line 424, in _commitResources</li>
> <li>  Module ZODB.Connection, line 462, in commit</li>
> <li>  Module ZODB.Connection, line 503, in _commit</li>
> <li>  Module ZODB.Connection, line 526, in _store_objects</li>
> <li>  Module tempstorage.TemporaryStorage, line 200, in store</li>
> </ul>ConflictError: 
> database conflict error (oid 0x0944, class BTrees._OOBTree.OOBTree, 
> serial this txn started with 0x035f134dc11a2977 2005-08-03 12:29:45.258327, serial 
> currently committed 0x035f1357051c7199 2005-08-03 12:39:01.197916)
> 
> 
> So far I see that DCOracle2 version of my app caused 9 errors for 
> the same scenario with 50 users. These are conflict errors with 
> DCOracle2.DA.Procedure and in ZEO.ClientStorage...
>