[Zope-dev] catalog performance: query plan

[Roché Compaan]

On Mon, 2008-11-10 at 18:38 +0200, Hedley Roos wrote:
> Kinda pointless for me to continue since this is turning into a
> Plone-specific discussion on zope-dev. But at least the whole exercise
> has forced us to look in detail into how all these indexes affect
> performance with a zodb with many many objects.
> 
> Roche investigated Tesdal's queryplan today end it seems to solve
> nearly all our performance problems. He'll have to elaborate.

Well that is not really true. What solved our performance problems is
not querying on object_implements and getEffective_or_created. I have
previously done benchmarks with query plan and it didn't make any
noticeable difference.

What might be true or is becoming more likely is that indexes are used
where they don't fit the use case rather than that the indexes
themselves need optimisation.

-- 
Roché Compaan
Upfront Systems                   http://www.upfrontsystems.co.za