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Date: Wed, 24 Feb 2010 22:11:02 -0500
From: Rik van Riel <riel@redhat.com>
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To: Wu Fengguang <fengguang.wu@intel.com>
CC: Andrew Morton <akpm@linux-foundation.org>,
       Jens Axboe <jens.axboe@oracle.com>, Li Shaohua <shaohua.li@intel.com>,
       Clemens Ladisch <clemens@ladisch.de>,
       Chris Mason <chris.mason@oracle.com>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Olivier Galibert <galibert@pobox.com>, Vivek Goyal <vgoyal@redhat.com>,
       Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>,
       Matt Mackall <mpm@selenic.com>, Nick Piggin <npiggin@suse.de>,
       Linux Memory Management List <linux-mm@kvack.org>,
       linux-fsdevel@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 01/15] readahead: limit readahead size for small devices
References: <20100224031001.026464755@intel.com> <20100224031053.737437080@intel.com>
In-Reply-To: <20100224031053.737437080@intel.com>
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On 02/23/2010 10:10 PM, Wu Fengguang wrote:
> Linus reports a _really_ small&  slow (505kB, 15kB/s) USB device,
> on which blkid runs unpleasantly slow. He manages to optimize the blkid
> reads down to 1kB+16kB, but still kernel read-ahead turns it into 48kB.

> CC: Li Shaohua<shaohua.li@intel.com>
> CC: Clemens Ladisch<clemens@ladisch.de>
> Acked-by: Jens Axboe<jens.axboe@oracle.com>
> Tested-by: Vivek Goyal<vgoyal@redhat.com>
> Tested-by: Linus Torvalds<torvalds@linux-foundation.org>
> Signed-off-by: Wu Fengguang<fengguang.wu@intel.com>

Acked-by: Rik van Riel <riel@redhat.com>