[Zope] urgent stability problem on production site

[Chris McDonough]

> A conflict error on its own just shows that you have a lot of load to
> handle. So this should not kill the Zope process. But in my experience, CST
> never worked without problems. Load errors and conflicts happened rather
> frequently. I'd suggest upgrading to 2.5 and the new session stuff soon,
> though this might also cause new problems on other parts of the site, and
> certainly can not be done over night ...

Note that as far as CST (or ZODB in general) goes, load errors are 
usually bugs but conflict errors are normal.

Since Frank is able to run this thing in single-threaded mode and it 
works ok (it doesn't segfault), the problem is probably with a C 
extension somewhere that is not threadsafe.  CST is all Python code, so 
I doubt it's that (unless it's calling a library which is not 
threadsafe, but it uses only the stock Python libraries which we know 
are).  I suspect that it's either some piece of C code in Zope proper or 
Frank's database adapter.

- C