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Message-ID: <1327757611.7199.6.camel@edumazet-laptop>
Subject: Re: Bad SSD performance with recent kernels
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Wu Fengguang <wfg@linux.intel.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>, Jens Axboe <axboe@kernel.dk>,
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Date: Sat, 28 Jan 2012 14:33:31 +0100
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Le samedi 28 janvier 2012 à 20:51 +0800, Wu Fengguang a écrit :

> Would you please create a filesystem and large file on sda and run the
> tests on the file? There was some performance bug on reading the raw
> /dev/sda device file..

Hmm... latest kernel has the performance bug right now.

Really if /dev/sda is slow, we are stuck.

FYI, I started a bisection.