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Date: Fri, 5 Aug 2005 11:39:55 -0700
From: Stephen Pollei <stephen.pollei@gmail.com>
Reply-To: Stephen Pollei <stephen.pollei@gmail.com>
To: Christoph Lameter <christoph@lameter.com>
Subject: Re: [PATCH] kernel: use kcalloc instead kmalloc/memset
Cc: Roman Zippel <zippel@linux-m68k.org>,
       Arjan van de Ven <arjan@infradead.org>, Andrew Morton <akpm@osdl.org>,
       Pekka J Enberg <penberg@cs.helsinki.fi>, linux-kernel@vger.kernel.org,
       pmarques@grupopie.com, Linus Torvalds <torvalds@osdl.org>
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On 8/5/05, Christoph Lameter <christoph@lameter.com> wrote:

> Hmm. If we had kcmalloc then we may be able to add a zero bit to the slab
> allocator. If we would obtain zeroed pages for the slab then we may skip
> zeroing of individual entries. However, the cache warming effect of the
> current zeroing is then not occurring. Not sure if this would make sense
> but this is a possible optimization if we had kcmalloc.

Well there is kzalloc and kcalloc. I just thought a safe non-zeroing
version would be nice.
You could warm the cache with prefetch, but you'd need to profile the
diferent cases to see what is worth doing and what isn't.


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