[Zope-dev] where is Zope 2.5.1?

Leonardo Rochael Almeida leo@hiper.com.br
13 Mar 2002 16:44:25 -0300


On Wed, 2002-03-13 at 14:04, Brian Lloyd wrote:
> 
> The best way to help is to help get this (these) down to 
> a minimal, reproducable test case.

The problem is, as far as I could check, the crashes all happen inside
the gc, which runs orthogonal to the requests, so getting a
reproduceable test case is really hard.

> Getting there can be 
> tricky, but there are some things that we can try to find 
> out:
> 
>   - In the logs, is there any pattern to what is being 
>     accessed at the time of the crash? If there is a 
>     particular object or objects that seems to often be 
>     the last accessed before a crash, we can start looking 
>     at what PythonScripts the object uses.

No, crashes happen all over the map (most of the site runs the same
python scripts for authentication and inside ZClass instances)

> 
>   - Use the "big M" log to try to narrow down exactly what 
>     is happening at the time of the crash.

Will do, but since the crashes happen all over the map, I don't think
we'll be able to get much out of it

>   - Ensure that you are getting absolutely no "python scripts 
>     need to be recompiled" messages

Check!

> 
>   - Absolutely eliminate SQL db access as a cause (it sounds 
>     like we have proof of this now)

Check!


As someone else mentioned on this list, maybe if we could force the gc
to collect alligned with the requests (say, in the first phase of the
two-phase-commit transaction engine, or after the second phase) we could
get the crashes to be reproduceable, or at least more localized.

Also, as I pointed out before, since '-t 1' solves the crashes, if we
could incrementally reduce the contention area around the code, by
putting and successively removing locks around certain sections, we
might be able to track it down.

The problem is, I don't know enough about Zope code to know how to do
any of those things, and I suspect the other folks with crashes are in
the same situation.

Cheers, Leo

-- 
Ideas don't stay in some minds very long because they don't like
solitary confinement.