From: Alasdair G Kergon <agk@redhat.com>
Subject: Re: regression: 100% io-wait with 2.6.24-rcX
Date: Tue, 22 Jan 2008 23:40:52 +0000
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Mel Gorman <mel@csn.ul.ie>,
	Fengguang Wu <wfg@mail.ustc.edu.cn>,
	Mike Snitzer <snitzer@gmail.com>,
	Peter Zijlstra <peterz@infradead.org>, jplatte@naasa.net,
	Ingo Molnar <mingo@elte.hu>, linux-kernel@vger.kernel.org,
	"linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>,
	James.Bottomley@steeleye.com, Jens Axboe <jens.axboe@oracle.com>,
	Milan Broz <mbroz@redhat.com>, Neil Brown <neilb@suse.de>
To: Martin Knoblauch <spamtrap@knobisoft.de>
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On Tue, Jan 22, 2008 at 07:25:15AM -0800, Martin Knoblauch wrote:
>   [root@lpsdm52 ~]# dmsetup table
> VolGroup00-LogVol02: 0 350945280 linear 104:2 67109248
> VolGroup00-LogVol01: 0 8388608 linear 104:2 418054528
> VolGroup00-LogVol00: 0 67108864 linear 104:2 384

The IO should pass straight through simple linear targets like that without
needing to get broken up, so I wouldn't expect those patches to make any
difference in this particular case.

Alasdair
-- 
agk@redhat.com