[Zope] DA threading issues (was: server instability: ZODB corruption?)

[Guido A.J. Stevens]

If I'm running current stable versions of Zope and Zope-MysqlDA, do I
need to consider threading issues or are these safely abstracted away
in the DA?

"Luis Cortes" <LCortes@IMEME.NET> writes:

>     It may just be the version of Zope you have ( with regard to the Thread
> problem ) there exists a version of zope that was known to cause the thread
> death problem.  You might want to check the patches or upgrade to a good
> version.

I'm running the Debian frozen release, i.e. 2.1.6 with security
patches. Do you have any specific references on the thread problem? I
find nothing on it in the changelogs I've found. Do I need to go to
2.2.0 for this? 

A seach on 'threading problem' turns up a hornet's nest of deep
technical shit. Most of those mails are a year old, is this still an
issue? As a developer, do I need to understand threading issues when
developing database accessing products, or may I safely assume that
threading, locking and transaction semantics are handled between the
Database Adapter and Zope itself?

I found a mail that says I should run Zope single-threaded when using
MySQL: http://lists.zope.org/pipermail/zope/1999-July/006487.html
Checking my installation, I find I have no threading option activated, 
which means I'll be running the default number of 4 threads. What will 
my server performance look like if I reduce this to 1 thread? Not
that I'm having such a wonderful performance now, having my pager go
off every hour :-(

Is there a way to allocate different threads to different SiteRoot
virtual websites, so I can lock a single site in a single thread but
let my installation as a whole still retain some multi-threading
performance?

:*CU#
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