[ZODB-Dev] Generational Caching

Tim Peters tim at zope.com
Tue Jun 7 23:05:55 EDT 2005


[Chris McDonough]
> One way to potentially soften the impact of cache busting by spiders
> might be to allow Zope to choose a particular ZODB connection based on
> request parameters (like sessionid or requesting ip address, or most
> likely user agent in the case of "legitimate" spiders).  This is a
> modification to Zope that would be largely independent of ZODB, however,
> so might be more appropriate to discuss on zope-dev.

I don't know what "generational caching" means anyway, so that sounds like a
fine idea to me too <wink>.

When Jeremy and I were looking at alternative ZEO cache designs, several
papers made the point that both recency and frequency of access "should be"
taken into account.  The ZODB memory cache is pure LRU now, considering only
recency.  Considering frequency of access too could/should be an effective
way to avoid giving undue weight to one-shot requests.  But that's a more
complicated cache design than pure LRU, so who knows if it would be a _net_
win.  Buying more RAM is an idea that just never gets old <wink>.



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