Date: Tue, 16 Jan 2007 12:51:14 -0800 (PST)
From: Christoph Lameter <clameter@sgi.com>
To: Paul Menage <menage@google.com>
cc: akpm@osdl.org, linux-kernel@vger.kernel.org,
       Nick Piggin <nickpiggin@yahoo.com.au>, linux-mm@kvack.org,
       Andi Kleen <ak@suse.de>, Paul Jackson <pj@sgi.com>,
       Dave Chinner <dgc@sgi.com>
Subject: Re: [RFC 8/8] Reduce inode memory usage for systems with a high
 MAX_NUMNODES
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On Tue, 16 Jan 2007, Paul Menage wrote:

> I was thinking runtime, unless MAX_NUMNODES is less than 64 in which
> case you can make the decision at compile time.
> 
> > 
> > If done at compile time then we will end up with a pointer to an unsigned
> > long for a system with <= 64 nodes. If we allocate the nodemask via
> > kmalloc then we will always end up with a mininum allocation size of 64
> > bytes.
> 
> Can't we get less overhead with a slab cache with appropriate-sized objects?

Ok but then we are going to have quite small objects. Plus we will have 
additional slab overhead per node.
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