From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christophe Varoqui <christophe.varoqui@gmail.com>
Subject: Re: dd slow while reading on multipathing,
 writing is fast
Date: Wed, 09 Feb 2011 12:03:13 +0100
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On mar., 2011-02-08 at 15:44 +0100, bart.coninckx@telenet.be wrote:
> Hi all,
> 
> something peculiar I cannot get my head round.
> I have a setup where a backup server connects to iSCSI LUNs over multipathing.
> While dd-ing to it, I get a spiffing 200 MB/sec, while reading it drops to 70 MB/sec. Local storage where I write the image onto is sufficiently fast.
> 
> Do you think this is multipathing related? I'm running the latest version from source.
> 
please send at least
- kernel version
- multipath tools version
- device map string