Hermann Himmelbauer wrote: > Hi, > Just by chance, I pressed the reload button of my browser for quite some > time, > so that my Zope3-based site was reloaded over and over. I was surprised to > find the following in the logs: > > 2008-10-20T18:45:15 WARNING ZopePublication Competing writes/reads > at /BSPSite/act/s/info: database conflict error (oid 0x0733, class > zope.session.session.SessionData) > > Can someone explain me why this happens, if this is something dangerous or if > I can forget about it? > > I tested the site with Apache Bench (ab2), with many concurrent requests and > could not reproduce the problem. > > So my wild guess is the following: > I use session.PersistentSessionDataContainer for my session, so every request > will probably read/write to some Zope3 container/btree. And then, for some > reasons these reads/writes compete, which leads to the above warning. If I > use AB2, there's no cookie, thus no session, hence the problem does not > arise. > > On the other hand, the zope root site (the Rotterdam ZMI) seems not to have > this problem, as it seems, I can't trigger this warning message with fast > reloads.
Presumably that site does not use sessioning so does not suffer from the same problem. Laurence _______________________________________________ Zope-Dev maillist - Zope-Dev@zope.org http://mail.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope )