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Subject: Re: [patch V3] percpu_counter: scalability works
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shaohua.li@intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "cl@linux.com" <cl@linux.com>, "npiggin@kernel.dk" <npiggin@kernel.dk>
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Date: Tue, 17 May 2011 15:00:23 +0200
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Le mardi 17 mai 2011 à 14:45 +0200, Tejun Heo a écrit :

> Given that _sum() is super-slow path and we have a lot of latitude
> there, 

Absolutely not. Its slow path yes, but not super-slow.

Dont change rules now ;)

Take a look at include/net/tcp.h and commit ad1af0fedba14f82b
(tcp: Combat per-cpu skew in orphan tests.)

If you guys make percpu_counter much slower, we'll just remove its use
in network stack, and there will be not a lot of users left.