On 3 July 2013 12:56, Amit Kapila wrote:
My perspectives here would be
* BufFreelistLock is a huge issue. Finding a next victim block needs to
beMy perspectives here would be
* BufFreelistLock is a huge issue. Finding a next victim block needs to
an O(1) operation, yet it is currently much worse than that. Measuring
contention on that lock hides that problem, since having shared buffers
lock up for 100ms or more but only occasionally is a huge problem, even ifit
doesn't occur frequently enough for the averaged contention to show as an
issue.To optimize finding next victim buffer, I am planning to run the clock
sweep in background. Apart from that do you have any idea to make it closer
to O(1)?
back last few CFs of 9.3
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