Messages in this thread | | | From | Linus Torvalds <> | Date | Mon, 24 Sep 2012 20:32:43 -0700 | 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 Mon, Sep 24, 2012 at 8:20 PM, Mike Galbraith <efault@gmx.de> wrote: > > Yes. Cross wiring traverse _start_ points should eliminate (well, damp) > bounce as well without killing the 1:N latency/preempt benefits of large > L3 packages.
Yes, a "test buddy first, then check the other cores in the package" hybrid approach might be reasonable.
Of course, that's effectively what the whole "prev_cpu" thing is kind of supposed to also do, isn't it? Because it's even lovelier if you can avoid bouncing around by trying to hit a previous CPU that might just have some of the old data in the caches still.
Linus
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