On 3 July 2013 12:56, Amit Kapila <amit.kap...@huawei.com> wrote:
> >My perspectives here would be > > > * BufFreelistLock is a huge issue. Finding a next victim block needs to > be > 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 if > it > > 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)? > Yes, I already posted patches to attentuate the search time. Please check back last few CFs of 9.3 -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services
