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Subject: Re: [PATCH v2] proc:  speedup /proc/stat handling
From: Eric Dumazet <eric.dumazet@gmail.com>
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Le mardi 24 janvier 2012 à 17:27 -0800, Andrew Morton a écrit :

> I had a fiddle on an 8-way x86_64 machine.  I'm unable to demonstrate
> any improvement for either of
> 
> time (for i in $(seq 1000); do; cat /proc/self/stat > /dev/null; done)
> time (for i in $(seq 1000); do; cat /proc/1/stat > /dev/null; done)
> 
> oh well.

What size is /proc/stat ?

wc -c /proc/stat

If under 4096, there is no problem with existing code.

I had the problem on a 16-way machine.