Linux Device Mapper development
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From: Christophe Varoqui <christophe.varoqui@gmail.com>
To: device-mapper development <dm-devel@redhat.com>
Subject: Re: dd slow while reading on multipathing, writing is fast
Date: Wed, 09 Feb 2011 12:03:13 +0100	[thread overview]
Message-ID: <1297249393.29348.17.camel@zezette> (raw)
In-Reply-To: <638331349.4388161297176246800.JavaMail.root@tendai.telenet-ops.be>

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

  reply	other threads:[~2011-02-09 11:03 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <315312316.4387891297176180905.JavaMail.root@tendai.telenet-ops.be>
2011-02-08 14:44 ` dd slow while reading on multipathing, writing is fast bart.coninckx
2011-02-09 11:03   ` Christophe Varoqui [this message]
2011-02-09 11:22   ` Bryn M. Reeves
2011-02-10 19:48     ` Bart Coninckx

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