Messages in this thread | | | Date | Tue, 23 Mar 2010 12:54:47 -0700 (PDT) | From | Linus Torvalds <> | Subject | Re: [Bugme-new] [Bug 15618] New: 2.6.18->2.6.32->2.6.33 huge regression in performance |
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On Tue, 23 Mar 2010, Anton Starikov wrote:
> > On Mar 23, 2010, at 6:45 PM, Linus Torvalds wrote: > > > > > > > On Tue, 23 Mar 2010, Ingo Molnar wrote: > >> > >> It shows a very brutal amount of page fault invoked mmap_sem spinning > >> overhead. > > > > Isn't this already fixed? It's the same old "x86-64 rwsemaphores are using > > the shit-for-brains generic version" thing, and it's fixed by > > > > 1838ef1 x86-64, rwsem: 64-bit xadd rwsem implementation > > 5d0b723 x86: clean up rwsem type system > > 59c33fa x86-32: clean up rwsem inline asm statements > > > > NOTE! None of those are in 2.6.33 - they were merged afterwards. But they > > are in 2.6.34-rc1 (and obviously current -git). So Anton would have to > > compile his own kernel to test his load. > > > Applied mentioned patches. Things didn't improve too much.
Yeah, I missed at least one commit, namely
bafaecd x86-64: support native xadd rwsem implementation
which is the one that actually makes x86-64 able to use the xadd version.
Linus
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