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GENERIC_TIME patchset for x86_64

From:  john stultz <johnstul@us.ibm.com>
To:  Andrew Morton <akpm@osdl.org>, Andi Kleen <ak@suse.de>
Subject:  [PATCH 0/5][time][x86_64] GENERIC_TIME patchset for x86_64
Date:  Tue, 19 Dec 2006 20:20:39 -0500
Cc:  john stultz <johnstul@us.ibm.com>, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@elte.hu
Archive-link:  Article, Thread

Andrew, Andi,

	I didn't hear any objections (or really, any comments) on my 
last release, so as I mentioned then, I want to go ahead and push this 
to Andrew for a bit of testing in -mm. Hopefully targeting for 
inclusion in 2.6.21 or 2.6.22.

Here's the performance data from the last release:

Vanilla TSC:
149 nsecs per gtod call
367 nsecs per CLOCK_MONOTONIC call
288 nsecs per CLOCK_REALTIME call
Vanilla ACPI PM:
1272 nsecs per gtod call
1335 nsecs per CLOCK_MONOTONIC call
1273 nsecs per CLOCK_REALTIME call

GENERIC_TIME TSC:
149 nsecs per gtod call
304 nsecs per CLOCK_MONOTONIC call
275 nsecs per CLOCK_REALTIME call
GENERIC_TIME ACPI PM:
1273 nsecs per gtod call
1275 nsecs per CLOCK_MONOTONIC call
1273 nsecs per CLOCK_REALTIME call

So almost no performance change.

New in the current C8 release:
o Synced up w/ 2.6.20-rc1
o Added a few small cleanups from Ingo

Let me know if you have any thoughts or comments!

thanks again!
-john

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