Messages in this thread | | | Subject | Re: PostgreSQL pgbench performance regression in 2.6.23+ | From | Mike Galbraith <> | Date | Thu, 22 May 2008 12:34:25 +0200 |
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On Thu, 2008-05-22 at 11:05 +0200, Mike Galbraith wrote: > On Thu, 2008-05-22 at 13:58 +0530, Dhaval Giani wrote:
> > Can you try with 2.6.26-rc? There is minimal load balancing for group > > scheduling till 25, which might explain the lack of scalability. > > I'm playing with it now, it's tweakable with migration cost. This > testcase is funky. It can't generate enough work to keep CPUs busy for > spit, and can't saturate my little quad with any kernel I've tried.
Heh, watch this. No tweaking.
(Nadia's ipc/idr patches are applied though, to see if the high end improves over previous runs with various kernels, and it does seem to.)
2.6.26-smp x86_64 1 10014.774797 2 9791.395302 3 10575.369296 4 9763.183251 5 10160.274262 6 9893.174179 8 9566.978464 10 10294.456456 15 9444.100540 20 9137.878618 30 8277.795499 40 7925.824428 50 7646.644285
nail postgres to CPUs1-3 nail pgbench to CPU0
2.6.26-smp x86_64 1 10900.959982 2 15976.870604 3 24661.322669 4 25347.141780 5 25893.815676 6 26756.414839 8 25399.018582 10 26172.878669 15 25542.082746 20 25090.381828 30 24270.301103 40 23405.867336 50 21926.223083
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