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From: Ingo Oeser <ioe-lkml@rameria.de>
To: Wu Fengguang <wfg@mail.ustc.edu.cn>
Subject: Re: [PATCH 4/5] readahead: backoff on I/O error
Date: Sat, 10 Jun 2006 20:33:45 +0200
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Cc: Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org,
       Michael Tokarev <mjt@tls.msk.ru>, Jens Axboe <axboe@suse.de>
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Hi Fengguang,

On Friday, 9. June 2006 10:08, Wu Fengguang wrote:
> Backoff readahead size exponentially on I/O error.
 
> With this patch, retries are expected to be reduced from, say, 256, to 5.
 
1. Would you mind to push this patch to -stable?

Reason: If killing a drive was hit in the field, this should be critical 
	enough.

2. Could you disable (at least optionally) read ahead complety 
  on the first IO error?

Reason: In a data recovery situation (hitting EIO quite often, 
	but not really sequentially) readahead is counter productive.
	E.g. trying to save an old CD with the cdparanoia software.


Regards

Ingo Oeser