slow down dd - how?
glarkin at FreeBSD.org
Thu Jul 8 17:28:11 UTC 2010
-----BEGIN PGP SIGNED MESSAGE-----
David Kelly wrote:
> On Thu, Jul 08, 2010 at 06:44:38PM +0200, Roland Smith wrote:
>> On Thu, Jul 08, 2010 at 05:50:52PM +0200, Jozsi Avadkan wrote:
>>> How can I slow down dd?
>> Play with the block size parameter (bs). Smaller block sizes means more
>> reads. The default is 512 bytes, which is very small.
>>> I don't want to slow down the pc, when generating a big file [~40
> I don't think Jozsi wants to burn more CPU cycles, just slow the
> process. Perhaps to attract less attention? Or interfere less with other
> Nice(1) is a good start but rtprio(1) is probably where he should look.
> Also consider that writing a program of your own to serve as a slow pipe
> shouldn't be very hard. Think it would be a good exercise as an
> introduction to Unix programming. Simply copy stdin to stdout with a
> usleep(3) between. Pipe dd through your slowpipe program.
> Someone else has probably written a slow pipe. I haven't looked.
Indeed someone has, and I ported it a few months back:
http://www.freshports.org/sysutils/pmt. Check the "throttle" subcommand.
I also use idprio(1)
schedule processes that I don't want interfering with the rest of the
Hope that helps,
http://www.FreeBSD.org/ - The Power To Serve
http://www.sourcehosting.net/ - Ready. Set. Code.
http://twitter.com/sourcehosting/ - Follow me, follow you
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
-----END PGP SIGNATURE-----
More information about the freebsd-questions