[Zope] Need Caching advice for CMF site ...

[Lynn Walton]

If we have a cmf based site with over 500 pages that are
CMFDefault.Documents  and we are using ZEO with 3 Zope Clients because
we have 3 servers in a server farm behind a content switch that does
loadbalancing,   We're trying to understand all our caching options so
we can avoid all 3 clients always hitting the ZEO Server since that sort
of defeats the purpose of it being load balanced.   Almost of the 500
pages are of a nature that they can be cached since they are not dynamic
in the "personalization" sense.  (We aren't using the CMF for it's
portal like (member join) abilities ... but rather for it's separation
of content and workflow abilities for a limited number of employees to
update content. Aside from the limited number of employees we set up as
owners w/ local roles for maintaining stuff, those hitting our site are
always "Anonymous", and the info isn't personalized.)

We're thinking about going with mod_proxy's cache abilities because
we're using Stronghold which isn't up to Apache 2 yet to use mod_cache.
But where I'm confused is about the layer's of caching available in
zope.  I've tried to read up .. but can't quite tell when it's advised
nor how to make use of zope's caching abilities?

For instance in a client .. under database management, cache parameters
I see this (which I've never messed with so it must be by default):

Total number of objects in the database             20518
Total number of objects in all caches                    2100
Target Size
400
Target max time between accesses                           60

Can someone point me to understanding if this level of caching stops the
client from making the trip to the ZODB on the ZEO Server.  Does is make
the mod_proxy way less necessary?  How are they different?  What else
should I know to make these decisions?  Do the needs for caching of a
CMF site differ from a non CMF site, since every CMF content object is
having to have a skin applied when it's requested?

Thanks,
Lynn