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Date: Tue, 03 Apr 2007 15:17:40 -0400
From: Phillip Susi <psusi@cfl.rr.com>
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To: Mark Lord <lkml@rtr.ca>
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       linux-kernel@vger.kernel.org
Subject: Re: Lower HD transfer rate with NCQ enabled?
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Mark Lord wrote:
> But WD drives, in particular the Raptor series, have a firmware "feature"
> that disables "drive readahead" whenever NCQ is in use.

Why is this an issue?  Shouldn't the kernel be sending down its own 
readahead requests to keep the disk busy?