Date: Wed, 12 Mar 2008 17:22:21 -0400
From: Rik van Riel <riel@redhat.com>
To: "J.C. Pizarro" <jcpiza@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: Re: linux+glibc memory allocator, poor performance
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On Wed, 12 Mar 2008 21:09:04 +0100
"J.C. Pizarro" <jcpiza@gmail.com> wrote:

> Assume a SMP system that has 8 CPUs. The main problem of requesting
> pages is the BKL (Big Kernel Lock) in this SMP system used for mutual
> exclusion of the shared resource (the memory).
> 
> To solve this major problem, i propose you freely to allocate 8 local caches
> of (e.g.) 2 MiB each CPU (total 2MiB x 8 CPUs = 16 MiB) acting as
> 8 producer buffers for globally many consumer tasks (e.g. >= 20).
> 
> When the some producer buffer is empty then it does unfrequently BKL to
> allocate another 2 MiB more from the shared resource (the memory).

You really should read the source code before proposing ideas.

The kernel has done roughly what you describe since a little before
2.6.0.

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