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To: "Martin J. Bligh" <mbligh@aracnet.com>
cc: torvalds@osdl.org, linux-kernel@vger.kernel.org,
       Andy Whitcroft <apw@shadowen.org>, akpm@osdl.org
Subject: Re: [PATCH] Permit inode & dentry hash tables to be allocated >
 MAX_ORDER size
References: <263jX-5RZ-19@gated-at.bofh.it> <262nZ-56Z-5@gated-at.bofh.it>
	<263jX-5RZ-17@gated-at.bofh.it>
From: Andi Kleen <ak@muc.de>
Date: Sat, 12 Jun 2004 02:21:28 +0200
In-Reply-To: <263jX-5RZ-17@gated-at.bofh.it> (Martin J. Bligh's message of
 "Sat, 12 Jun 2004 01:10:09 +0200")
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"Martin J. Bligh" <mbligh@aracnet.com> writes:
>
> Allocating the big-assed hashes out of bootmem seems much cleaner to me,
> at least ...

Machines big enough that such big hashes make sense are probably NUMA.
And on NUMA systems you imho should rather use node interleaving vmalloc(),
not a bit physical allocation on a specific node for these hashes. 
This will avoid memory controller hot spots and avoid the problem completely.
Likely it will perform better too.

-Andi