[Zope] Large jumps of memory use increase, and seeking overall understanding of memory use

[Maciej Wisniowski]

> Serving from cache still means they need to be touched at least once to
> get them into the cache, and (in case of normal caching behavior) they
> will be touched again once the cached record expires. 
Yes, right. I tried to write this with 'always':
"not served (always) directly by Zope/Plone instance" :)

> Caching will not
> make any difference to memory behavior I'd say.
I'm not expert here, so I might be wrong but AFAIK
Zope instance loads 'touched' objects from ZODB into cache.
Each ZODB connection has its own cache, so having object
touched more than once may cause it is loaded to more than one
cache.

The same will possibly be with multiple ZEO clients. External
cache will save them from being touched (sometimes even once).

ZODB connections cache is cleaned sometimes, so it should
flush objects that are old and possibly save some memory then.

I don't know whether amount of memory used because of above is huge
enough to cause described problem. It's just a though.

Feel free to correct me if I'm wrong.

-- 
Maciej Wisniowski