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From Øystein Grøvlen <Oystein.Grov...@Sun.COM>
Subject Re: out of memory when writing blobs
Date Wed, 14 Mar 2007 15:58:48 GMT
For tables with Blob or Clob columns, the default page size for the will 
be 32 kB.
(Ref. http://db.apache.org/derby/docs/dev/tuning/ctunperf816059.html )

--
Øystein

Anders Morken wrote:
> Anders Morken:
>>  [...] the page size (Seemed to be 32K in this case [...]
> 
> Aha. Those 32 kilobyte pages were "overflow pages", created to hold
> rows that won't fit on a regular page. The regular pages were 4
> kilobytes, the default size, but obviously those 6 megabyte blobs had
> to be split across a few overflow pages. =)
> 
> That explains why blob workloads suddenly consume a lot more memory than
> regular workloads with few (if any) overflow pages. Maybe this is
> common knowledge, but I just hadn't realized. =)
> 
> Sorry for the noise, just wanted to clear up (my own) confusion. =)
> 


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