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From: ebiederm@xmission.com (Eric W. Biederman)
To: William Lee Irwin III <wli@holomorphy.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>,
       Christoph Lameter <clameter@sgi.com>, linux-kernel@vger.kernel.org,
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       Badari Pulavarty <pbadari@gmail.com>,
       Maxim Levitsky <maximlevitsky@gmail.com>
Subject: Re: [00/17] Large Blocksize Support V3
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Date: Thu, 26 Apr 2007 12:21:24 -0600
In-Reply-To: <20070426145310.GH19966@holomorphy.com> (William Lee Irwin, III's
	message of "Thu, 26 Apr 2007 07:53:10 -0700")
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William Lee Irwin III <wli@holomorphy.com> writes:

> On Thu, Apr 26, 2007 at 05:42:17PM +1000, Nick Piggin wrote:
>> Actually, I don't know why people are so excited about being able to
>> use higher order allocations (I would rather be more excited about
>> never having to use them). But for those few places that really need
>> it, I'd rather see them use a virtually mapped kernel with proper
>> defragmentation rather than putting hacks all through the core code.
>
> In memory as on disk, contiguity matters a lot for performance.

Not nearly so much though.  In memory you don't have seeks to avoid.
On disks avoiding seeks is everything.

Eric