Messages in this thread | | | From | pageexec@freemail ... | Date | Mon, 06 Jun 2011 18:19:36 +0200 | Subject | Re: [PATCH v5 8/9] x86-64: Emulate legacy vsyscalls |
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On 6 Jun 2011 at 17:59, Ingo Molnar wrote:
> > > FYI, incredible amount of work has gone into making pagefaults as > > > fast and scalable as possible. > > > > i wasn't talking about scalability (it's irrelevant anyway here), > > only speed. [...] > > Which part of "fast and scalable" did you not understand?
uhm, not sure why you're so worked up here. is it because i said 'scalability' was completely irrelevant for the nx vsyscall page approach? elaborate!
> Just a couple of days ago i noticed a single cycle inefficiency in > the pagefault fastpath, introduced in the 3.0 merge window. I > requested (and got) an urgent fix for that:
so you must have measurements. what's the mentioned page faults take in cycles before/after your fix? what's a normal int xx path take?
> So i ask you again, what is your basis for calling the #PF path on > Linux a 'slowpath'? Is Linus's and my word and 5 years of Git history > showing that it's optimized as a fastpath not enough proof for you?
which part of
> you must have realized by now that slow/fast path in this context were > relative to int xx vs. pf processing.
did you not understand? do you have "Linus's and my word and 5 years of Git history" to show that pf processing is seriously that much faster than int xx processing?
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