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Date: Fri, 9 Jul 2010 20:09:27 +0200
From: Thomas <fwd@gothschlampen.com>
To: Robert Bonomi <bonomi@mail.r-bonomi.com>
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Cc: freebsd-questions@freebsd.org
Subject: Re: slow down dd - how?
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On Fri, Jul 09, 2010 at 01:44:00AM -0500, Robert Bonomi wrote:

Hi,

> > > How can I slow down dd?
> >
> > you could use some creative shellscripting (probably in addition to idprio):
> >
> > dd if=/dev/zero bs=1024k | ( dd bs=1024k count=10; sleep 3 ) | dd bs=1024k of=/dev/somewhere
> >
> > This pauses for 3 seconds for every 10MB written. ...
> 
> I must be missing something. 
> 
> Doesn't that "dd ... ; sleep" in the sub-shell need to be in a _loop_ of some 
> sort?

You're absolutely right. I probably should get more sleep. Of course it needs
to be in a loop, something like

"( while dd bs=1024k count=10; do sleep 3; done )"

should do the trick. Sorry for the confusion.


Regards
Thomas