Messages in this thread | | | Date | Fri, 14 Sep 2012 23:45:32 +0200 | From | Borislav Petkov <> | Subject | Re: 20% performance drop on PostgreSQL 9.2 from kernel 3.5.3 to 3.6-rc5 on AMD chipsets - bisected |
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On Fri, Sep 14, 2012 at 11:40:43PM +0200, Peter Zijlstra wrote: > Hmm, cute. What kind of machine did you test it on? Nikolay's machines > look to be smallish AMD X6 or ancient Intel c2d (the patch will indeed > have absolutely no effect on a dual core).
Yep, I took an X6 too. So it's a single-socket, 6-core AMD, F10h.
> I'll see about running pgbench on a bigger Intel tomorrow if Mike > doesn't beat me to it.
Can try that too on one of the bigger machines I have, if needed.
> The problem the patch is trying to address is not having to scan an > entire package for idle cores on every wakeup now that packages are > getting stupid big. > > Regressing Postgres otoh isn't nice either.. > > Anyway, I guess I'm fine with nixing this patch until we figure out > something smarter.. > > I'm also curious to know wth postgres does that this patch makes such a > big difference...
I'm using 9.1 in Debian testing while Nikolay is using 9.2.
Thanks.
-- Regards/Gruss, Boris.
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