[Zope-dev] More signal 11 restarts....

Matthew T. Kromer matt@zope.com
Wed, 05 Dec 2001 15:10:03 -0500


Leonardo Rochael Almeida wrote:

>
>It's not fixed, but we managed to make it bearable so as not to lose the
>client.
>
>by replacing LoginManager with exUserFolder we managed to bring down the
>zope restart time from 5 min (we have a HUGE Data.fs) to 20 secs, and by
>installing ZEO we brought down the restart time to between 2 and 8 secs.
>By increasing the caching of requests we managed to increase the time
>between restart from 15 min to 2 hours. That and a nicely formated
>Apache error page for Proxy Errors, for the lucky bastards who happen to
>hit the server in the exactly 2 seconds of restart, managed to calm down
>the client enough for us to breath.
>
>I'll try the requestprofiler tip Chris gave, but I don't have much hope,
>since we use mysql for authentication and the site is authenticated
>mostly everywhere.
>
>We are seriously considering droping mysql for postgresql.
>
>	Cheers, Leo
>


Leo,

Are you comfortable with hooking up gdb to Zope to try to catch this?  I 
suspect, but do not know, that the MySQL python adapter is probably  not 
doing something right w.r.t. memory management.  Unfortunately, it is 
probably also the case that the problem only occurs with high-volume 
traffic -- particularly if it is a timing related bug.

We have not been able to reproduce this problem in any deterministic way 
-- and the only people who seem to have it are those who are heavy MySQL 
users; it makes me think there is something in the adapter which is not 
behaving the same way under Python 2.1 than it did under Python 1.5.2. 
 I have not looked at the adapter, so I'm making a few guesses as what 
is going wrong.