[ZODB-Dev] Very slow restarts with ZEO 2 ...

[Guido van Rossum]

> While the ZEO clients had started up and restarted almost immediately (5-10
> secs maximum for a start without having to rebuild the cache files), ZEO 2
> clients take up to half a minute.
> 
> This is not a problem for the production servers, as they usually won't
> restart frequently. But for development this is not so nice. My first guess
> was that ZEO 2 does some consistency checks on the cache files or so, as it
> spends a considerable amount of time after connecting to the ZEO server,
> which still happens almost instantly.
> 
> Could I get some hints on this? Can startup time be optimized by switching
> off some "paranoid" option or so? And what exactly might cause these startup
> times?
> 
> The database that is served is around 1-2 GB and the cache files are rather
> large, too (200 MB and more).

If your ZEO cache files are persistent, the cache verification may
explain this (though I'm not sure why it would be slower than with ZEO
1 -- that also does cache verification).

If you don't know, please show your custom_zodb.py.

--Guido van Rossum (home page: http://www.python.org/~guido/)