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Subject: Re: Intel P6 vs P7 system call performance
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "H. Peter Anvin" <hpa@transmeta.com>
Cc: Linus Torvalds <torvalds@transmeta.com>,
       Dave Jones <davej@codemonkey.org.uk>, Ingo Molnar <mingo@elte.hu>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Tue, 2002-12-17 at 19:12, H. Peter Anvin wrote:
> The complexity only applies to nonsynchronized TSCs though, I would
> assume.  I believe x86-64 uses a vsyscall using the TSC when it can
> provide synchronized TSCs, and if it can't it puts a normal system call
> inside the vsyscall in question.

For x86-64 there is the hpet timer, which is a lot saner but I don't
think we can mmap it


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