[Zope-dev] Conflict errors on BDBMinimal storage

[Chris McDonough]

Hi Dr. Wagner,

> thanks for the hint with minimal storage. however the same problem 
> occurs with filestorage and is even worse.
> 
> we know very well, that we cannot avoid the appearance of conflict 
> errors in particular with zeo, and we understand what causes them.
> 
> what wonders us is, that we find some contributions about this errors in 
> the mailing lists, but no one seems to have a real problem with it. but 
> we have! we are not worried about some errors appearing in a log, but we 
> are using plone2 witch currently 30 concurrent authenticated users, so 
> that this error occurs permanently, thus decreasing system performance 
> due to several retries and moreover leading to very frequent nasty 
> 'POS.Exception Errors' in the browser, whenever four successive tries 
> fail (almost every 100. request).
> 
> this is not acceptable, and i  wonder wheter there are any plone sites 
> with more than a handful of authenticated users that experience the same 
> problem.  we found that one (there are more) product responsible for it 
> is the placeless translation service, which heavily writes to the session.

Are you using ZEO for your session storage or are you using a local
storage?  (You hint at it above but you don't actually say one way or
the other.)

> so we desperately need a solution for this problem, maybe uncouple the 
> session of the locking mechanism or whatever, and this should be a 
> problem that should be addressed by the core team. because this is a 
> strong reason (and so far the only one) to avoid using zope/plone in a 
> large user environment.

I also need reliable sessioning for my own customers, so I am working
towards fixing the issues I know about.  But the issues I know about may
not be the same issues as those that you want fixed.  You can ensure
your issues are addressed by devoting resources towards the problem, be
that time+expertise or money or both.

- C