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From Knut Anders Hatlen <Knut.Hat...@Sun.COM>
Subject Re: initial page allocation versus incremental allocation
Date Tue, 03 Mar 2009 08:27:51 GMT
Brian Peterson <dianeayers@verizon.net> writes:

> 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.

I haven't tested that it actually works, but it appears to be referenced
in FileContainer.createInfoFromProp():

	PreAllocSize = 
		PropertyUtil.getServiceInt(tc, createArgs,
				RawStoreFactory.PRE_ALLOCATE_PAGE,
				MIN_PRE_ALLOC_SIZE,
				MAX_PRE_ALLOC_SIZE,				   
				DEFAULT_PRE_ALLOC_SIZE /* default */);

If it turns out that setting the property works, we should probably try
to get it into the documentation, as it looks like it could be useful.

-- 
Knut Anders

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