On 8/8/21 9:02 AM, David Rowley wrote:
On Sat, 7 Aug 2021 at 12:10, Tomas Vondra <tomas.von...@enterprisedb.com> wrote:
On 8/6/21 3:07 PM, David Rowley wrote:
All of the tests show that the patches to improve the allocation
efficiency of generation.c don't help to improve the results of the
test cases. I wondered if it's maybe worth trying to see what happens
if instead of doubling the allocations each time, quadruple them
instead. I didn't try this.
I doubt quadrupling the allocations won't help very much, but I suspect
the problem might be in the 0004 patch - at least that's what shows
regression in my results. Could you try with just 0001-0003 applied?
But 0004 only changes the logic which controls the threshold of when
we allocate an oversized chunk. It looks like the threshold is 512KB
with the 0004 patch. My test is only doing a maximum allocation of
296 bytes so will never allocate an oversized chunk.
Can you explain why you think 0004 would cause performance regressions?
It's based solely on results of my benchmarks, where this patch seems to
cause performance regression. I agree it's a bit bizzare, considering
what the patch does.
regards
--
Tomas Vondra
EnterpriseDB: http://www.enterprisedb.com
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