From: "H. Peter Anvin" <hpa@zytor.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Shaohua Li <shaohua.li@intel.com>,
lkml <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
Andi Kleen <andi@firstfloor.org>,
"Chen, Tim C" <tim.c.chen@intel.com>
Subject: Re: [PATCH 1/2]percpu: introduce read mostly percpu API
Date: Tue, 19 Oct 2010 23:00:36 -0700 [thread overview]
Message-ID: <4CBE8584.10707@zytor.com> (raw)
In-Reply-To: <1287551880.2700.79.camel@edumazet-laptop>
On 10/19/2010 10:18 PM, Eric Dumazet wrote:
>
> Could you precisely describe why grouping together read mostly percpu
> variables is a win ? Especially when you add in your next patch a single
> variable ?
>
The logic is that those variables are less likely to end up dirty in the
cache. It is, however, much less of an issue for percpu variables,
since dirty lines there aren't quite so likely to bounce around.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
next prev parent reply other threads:[~2010-10-20 6:01 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-20 3:07 [PATCH 1/2]percpu: introduce read mostly percpu API Shaohua Li
2010-10-20 5:18 ` Eric Dumazet
2010-10-20 6:00 ` H. Peter Anvin [this message]
2010-10-20 7:35 ` Andi Kleen
2010-10-20 7:53 ` Eric Dumazet
2010-10-20 21:38 ` H. Peter Anvin
2010-10-20 21:42 ` H. Peter Anvin
2010-10-20 21:33 ` H. Peter Anvin
2010-10-20 23:06 ` [tip:x86/mm] percpu: Introduce a read-mostly " tip-bot for Shaohua Li
2010-10-21 1:38 ` Shaohua Li
2010-10-21 2:53 ` H. Peter Anvin
2010-10-21 5:33 ` Eric Dumazet
2010-10-21 5:54 ` H. Peter Anvin
2010-10-21 6:07 ` Eric Dumazet
2010-10-21 6:09 ` H. Peter Anvin
2010-10-21 6:17 ` Shaohua Li
2010-10-21 6:48 ` Eric Dumazet
2010-10-21 6:54 ` H. Peter Anvin
2010-10-21 6:10 ` H. Peter Anvin
2010-10-21 7:40 ` [tip:x86/mm] x86-32, percpu: Correct the ordering of the percpu readmostly section tip-bot for H. Peter Anvin
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