On Wed, May 30, 2012 at 8:57 PM, Murat Tasan <mmuurr@gmail.com> wrote:
> any insights here?
Have you tried running the slow option multiple times? According to
the explain output all of the time was accounted to the bitmap heap
scan. For the second explain plan the same node was fast. It looks to
me as the first explain on 8.4 was slow because the data was still on
disk. Raising work mem doubled the speed of the sort from 800ms to
400ms.
Regards,
Ants Aasma
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