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Date: Thu, 12 Jan 2006 06:59:10 -0600
From: "Matthew D. Fuller" <fullermd@over-yonder.net>
To: Christoph Kukulies <kuku@www.kukulies.org>
Message-ID: <20060112125910.GB20029@over-yonder.net>
References: <200601120948.k0C9mcqR092895@www.kukulies.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: increasing dd disk to disk transfer rate
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On Thu, Jan 12, 2006 at 10:48:38AM +0100 I heard the voice of
Christoph Kukulies, and lo! it spake thus:
> 
> dd if=/dev/ad2 of=/dev/ad3 conv=noerror

Give it a bigger blocksize (say, bs=1m or so) and it'll go a **LOT**
faster.


> My motherboard is an ASUS P4S8X with an on board promise controller
> (currently not in use). System disk is on IDE1 and the two 80GB
> disks are master/slave on IDE2 bus.

You'll get much better results by having each drive be master on its
own bus.



-- 
Matthew Fuller     (MF4839)   |  fullermd@over-yonder.net
Systems/Network Administrator |  http://www.over-yonder.net/~fullermd/
           On the Internet, nobody can hear you scream.