Date: Fri, 29 Jun 2007 00:00:39 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: David Miller <davem@davemloft.net>
cc: hugh@veritas.com, James.Bottomley@steeleye.com, rmk+lkml@arm.linux.org.uk,
       akpm@linux-foundation.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Containment measures for slab objects on scatter gather
 lists
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On Thu, 28 Jun 2007, David Miller wrote:

> Really, it would be great if we could treat kmalloc() objects
> just like real pages.  Everything wants to do I/O on pages
> but sometimes (like the networking) you have a kmalloc
> chunk which is technically just a part of a page.
> 
> The fact that there is no easy way to make this work is
> frustrating :-)

There is easy way: Allocate a page and just use the first N bytes. You can 
specify the bytes to be used when putting the memory onto the scatter 
gather list. This wastes memory but it works. You have real refcounting 
since you got a real page.

How frequent are these objects?

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