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- <li><em>date</em>: Mon Jan 10 19:19:46 2005</li>
- <li><em>from</em>: danscox at mindspring.com (Danny Cox)</li>
- <li><em>in-reply-to</em>: <<a href="msg00330.html">[email protected]</a>></li>
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- <li><em>subject</em>: [ale] Understanding dd and/or /dev/zero</li>
On Mon, 2005-01-10 at 16:54 -0500, Greg Freemyer wrote:
> I've noticed that I get a log of disk read activitity on /dev/hdc when I do
>
> dd if=/dev/zero of=/dev/hdc
>
> I'm using "iostat -d 5" to see the read activity, and it is really
> slowing down the above.
>
> I have no idea why there is disk read activity, and the machine is
> doing nothing else. Also if I kill the above dd, the read activity
> stops.
I don't know why you're seeing reads either, unless iostat is wrong, or
the kernel is.
As another data point, try bumping up the block size of the dd like
this:
dd bs=1024M if=/dev/zero of=/dev/hdc
and stand well back ;-).
--
kernel, n.: A part of an operating system that preserves the
medieval traditions of sorcery and black art.
Danny
</pre>
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<li><strong><a name="00336" href="msg00336.html">[ale] Understanding dd and/or /dev/zero</a></strong>
<ul><li><em>From:</em> greg.freemyer at gmail.com (Greg Freemyer)</li></ul></li>
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