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From <de...@segel.com>
Subject RE: initial page allocation versus incremental allocation
Date Mon, 02 Mar 2009 23:40:55 GMT
I think that the simple answer is that Cloudscape wasn't designed as a
general purpose relational database. Its target niche was embedded and
smaller apps.

 

So it sounds like the issue you were having is solved. That is, once you hit
your preset size, the default allocations is too small and its impacting
your ability to increase your table space.

 

It sounds like an enhancement to me.

 

BTW, if you want to 'hack' this to test the theory out, just change the
DEFAULT_PRE_ALLOC_SIZE constant in the File Container to be something like
1000.

Then run your test again.

 

  _____  

From: Brian Peterson [mailto:dianeayers@verizon.net] 
Sent: Monday, March 02, 2009 5:28 PM
To: 'Derby Discussion'
Subject: initial page allocation versus incremental allocation

 

I see that there's a property to allow configuring the number of pages to
initially allocate to a table, derby.storage.initialPages, but there isn't a
property to allow for setting the number of pages to allocate when
incrementally expanding the file container. It looks like RawStoreFactory
might've allowed for this with 

 

                public static final String PRE_ALLOCATE_PAGE =
"derby.storage.pagePerAllocation";

 

but this isn't reference by anything I can find.  FileContainer fixes the
incremental expansion to 8 pages with the DEFAULT_PRE_ALLOC_SIZE constant.

 

What was the reason for not allowing the pre-allocation setting to be
configurable? Were there adverse affects on FileContainer if it was
increased to something like 100 pages?

 

Brian

 


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