[Zope] Serious write-performance issue with multiple threads.

[Dieter Maurer]

Arnar Lundesgaard writes:
 > ...
 > The problem has been scarily easy to reproduce, and manifests itself
 > whenever multiple persons are working (writing articles etc). As long as
 > only one person is working on the site, it has the expected performance.
 > Not very fast, a few seconds per write operation, but acceptable.
 > However as soon as more people log in and start publishing, we often
 > experience hangs which may last for 10-15 minutes on write operations
 > that usually takes only a few seconds to perform. In this situation Zope
 > doesn't respond to any requests.
Maybe, there are "ConflictError"s. When they occur, Zope
automatically restarts the requests. I have some doubts that
Zope does it in a way that prevents a new "ConflictError" with high
probability. On the other hand, it is not too likely, that
the automatic repetition increases the time by almost two orders...


Dieter