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From Øyvind Harboe <oyvind.har...@zylin.com>
Subject Derby memory consumption with many databases
Date Thu, 07 Jan 2010 09:45:56 GMT
Did I understand correctly that  derby.storage.pageCacheSize is configured
per database?

Is there a way to set the page cache size for derby across all databases in
the JVM when running Derby in embedded mode?

Background:

We are running Derby in an application where there is one database per client.

Eventually we would want to update the database model to allow all clients
to be inside a single database, but that is a big undertaking.

Derby offers a great solution for us. We use it in embedded mode and have
one database per client.

However, memory consumption is getting out of hand now that we're reaching
hundreds of databases.

After taking a heap snapshot and examining memory usage, it looks like it is
the page cache that is causing the problem.

At any one time there are only a few databases active, so if Derby had a concept
of configuring maximum cache usage for the entire JVM, there would not be
a problem with the available memory.

-- 
Øyvind Harboe
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