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From "Laura Stewart" <scotsmat...@gmail.com>
Subject Optimizer questions [Derby 1397] - Need answers to close jira issue
Date Thu, 15 Jun 2006 17:24:04 GMT
On 6/12/06, Satheesh Bandaram <bandaram@gmail.com> wrote:
> Rick Hillegas wrote:
> > "If memory use is not a problem for your environment, set this
> > property to a high number; allowing the optimizer the maximum
> > flexibility in considering a join strategy queries involving large
> > queries leads to better performance. It can also be set to smaller
> > values for more limited environments."
> >
> > I can't find the name of this property on that page of the Tuning
> > Guide. I'm also confused about what we consider to be a "high number"
> > versus what we consider to be "smaller values". Would appreciate
> > advice here.
> The property it may be referring to is
> *derby.language.maxMemoryPerTable*. The default value is 1024 KB.
> Current default value is too small, so it would be a good tip for
> developers to know and tune this property. It would be great if Derby
> can configure this property value based on factors like max heap size,
> size of data cache and/or other parameters.
> If you are opening a documentation bug for other issue you found, may be
> you can include this omission as well.
> Satheesh

*** (LS) There are 2 issues in the Tuning Guide that need to be corrected.
Before the text can be updated there are several questions
that need to be answered.  The questions are posted in this thread and in
the jira issue #1397.  Can someone respond to these questions?

Laura Stewart

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