Date: Tue, 14 Jul 2009 13:25:38 +0900
From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
To: Paul Menage <menage@google.com>
Cc: Benjamin Blum <bblum@google.com>, Li Zefan <lizf@cn.fujitsu.com>,
       linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org,
       akpm@linux-foundation.org, serue@us.ibm.com
Subject: Re: [PATCH 3/3] Quick vmalloc vs kmalloc fix to the case where
 array  size is too large
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On Mon, 13 Jul 2009 21:04:32 -0700
Paul Menage <menage@google.com> wrote:

> On Mon, Jul 13, 2009 at 8:53 PM, KAMEZAWA
> Hiroyuki<kamezawa.hiroyu@jp.fujitsu.com> wrote:
> > Hmm, ok...then, if too much pids, you hit vmalloc()/vfree() problem again.
> > So, it's not good idea to use vmalloc/vfree here after all.
> >
> 
> Agreed, using vmalloc()/vfree() isn't a perfect solution, but at least
> the approach of kmalloc() for small allocations and vmalloc() for
> larger allocations solves the current problem (reading tasks/procs
> files can fail due to lack of contiguous kmalloc memory) without
> introducing overhead in the typical case.
> 
My point is 
 - More PIDs, More time necessary to read procs file.
This patch boost it ;) Seems like "visit this later again" ,or FIXME patch.

Thanks,
-Kame


> Paul
> 

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