Re: [PATCH] PM-Timer: doesn't use workaround if chipset is not buggy

[bert hubert <bert.hubert@netherlabs.nl>]

> This patch adds blacklist of buggy chip, and if chip is not buggy,
> this uses fast normal version instead of slow workaround version.

I can confirm that this patch solves the problem I originally complained
about. 

Timings of 10,000,000 gettimeofday calls on my pentium 4 3GHz (which I won
at OLS, ha!):

tsc
---
real    0m2.504s
user    0m0.700s
sys     0m1.804s

2.6.16-mainline
---------------
real    0m36.973s
user    0m1.440s
sys     0m34.130s

2.6.16-ogawa
------------
real    0m13.697s
user    0m1.712s
sys     0m11.117s

For reference, baseline 2.6.16 on my Athlon64 3200+
---------------------------------------------------
real    0m1.994s
user    0m0.990s
sys     0m0.990s

I'm still going to recommend all 'power' pdns_recursor users on single CPU
and not using frequency scaling to boot with clock=tsc - saves
2.2usec/packet. Or run on an opteron of course.

Thanks for the work everybody!

-- 
http://www.PowerDNS.com      Open source, database driven DNS Software 
http://netherlabs.nl              Open and Closed source services
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