On 12/08/2014 01:22 PM, Tom Lane wrote:
Adrian Klaver <adrian.klaver@xxxxxxxxxxx> writes:
I redid the test on my 32-bit machine, setting work_mem=16MB, and I got
comparable results to what I saw on the 64-bit machine. So, what I am
still am puzzled by is why work_mem seems to make the two paths
equivalent in time?:
If work_mem is large enough that we never have to go through
tbm_lossify(), then the recheck condition will never be executed,
so its speed doesn't matter.
Aah, peeking into tidbitmap.c is enlightening. Thanks.
(So the near-term workaround for Tim is to raise work_mem when
working with tables of this size.)
regards, tom lane
--
Adrian Klaver
adrian.klaver@xxxxxxxxxxx
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