[ZODB-Dev] [Enhancement] Common cache for mounted connections

[Toby Dickenson]

On Friday 30 September 2005 11:40, Dieter Maurer wrote:
> We have the need to mount dozens, if not hundreds of ZODBs in a single
> Zope instance.
> 
> With the current implementation, each ZODB connection has its own
> independent cache. This makes it very difficult to use the
> available memory efficiently for caching. As the caches are independent,
> a heavily used ZODB cannot use memory assigned to a lightly used ZODB.

Each ZODB version also has its own cache. There is already a mechanism for 
ensuring that lightly used versions do not hold on to memory indefinitely. 
That should be much easier, and might just be adequate.

One big disadvantage is that it does not enforce a strict upper limit on 
cache/memory usage, so memory usage will grow if all storages are frequently 
accessed.

-- 
Toby Dickenson