[Zope] Re: Zope vs Plone: performance issues!

[Jens Vagelpohl]

On 25 Jan 2006, at 10:42, Alexander Limi wrote:

> On Wed, 25 Jan 2006 00:11:04 -0800, Dario Lopez-Kästen  
> <dario at ita.chalmers.se> wrote:
>
>> Start by checking the ZODB cache numbers in the zope-conf file  
>> (too start simple). IIRC, the default is 5000 objects. Increase  
>> that to, say 50.000 or so (you mention that you have a busy site).
>
> Sorry, but this is not good advice. 5000 objects in the cache is  
> normally plenty, and you should look into caching the front-end  
> before you even consider this. 50K objects in the cache will eat *a  
> lot* of memory, and most likely cause swapping.
>
> Cache properly with Apache or Squid in front first, then  
> investigate the more complex settings.

Yes, just saying "change the setting to X" is definitely not good  
advice. But when it comes to twiddling knobs I would work from the  
bottom up instead of the other way around, meaning optimize the  
settings you have in Zope first. Even if you know you will use a  
cache you will want to make sure the backend is tuned properly.

jens