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From Kristian Waagan <Kristian.Waa...@Sun.COM>
Subject Re: order by
Date Thu, 02 Mar 2006 15:36:37 GMT
Thomas Vatter wrote:
> Kristian Waagan <Kristian.Waagan@...> writes:
> ...
> Hello Kristian,
> I'm doing this on a Windows XP system, I start all java processes with 
> -Xmx1024m, I had a try with 2048 but the process did not start so I stayed 
> with 1024. "Between 912 and 960" is the total usage for the machine, 
> read from the task-manager. I have thought about it, derbys pageSize 
> is 4k, I have increased pageCacheSize from 1.000 to 10.000, resulting 
> in 40mb steps, this would explain that memory "ends" before 1024 is 
> reached. Yes, I was unprecise for shortness with the word "record". 
> I should have said "record in the main database table" or "dataset".
> But you are right, a dataset (or line) in my spreadsheet has around 
> 30 fields only. I had the network server running on the described machine, 
> because I am testing how derby performes in the network situation, 
> because in the single user situation I have typically less data.
> tom

Okay, thank you for the answers.

Just to be clear, I would have tried running the Derby network server on 
a separate machine, and see where the the memory usage goes sky-high; 
the database machine or the application code machine.

You could also try running Derby with the default page cache size (1000 
pages ~ 4MB) and *not* alter the JVM memory options. Performance could 
go down, but if you are having problems with a memory leak it would show 
pretty fast by getting an OutOfMemoryException.


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