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From Knut Anders Hatlen <Knut.Hat...@Sun.COM>
Subject Re: [jira] Commented: (DERBY-801) Allow parallel access to data files.
Date Thu, 14 Sep 2006 10:13:38 GMT
"Suresh Thalamati (JIRA)" <derby-dev@db.apache.org> writes:

> 4) I noticed, there is new encryption buffer created on every
> writePage() call, if the database is encrypted. This may cause jvm
> peak memory usage increase, when there is a checkpoint, if there are
> lot of dirty pages in the cache and if garbage collection is not
> happening fast enough.  I hope this does not lead to out of memory
> errors!

This shouldn't cause out of memory errors. If the buffers are not
gc'ed fast enough, the checkpoint thread will be stalled until there
is enough memory for it to continue. Since the checkpoint thread only
writes one page at a time, the gc thread should be able to free all of
the old buffers.

Knut Anders

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