bug-coreutils
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Speed parameter for 'dd' command


From: Pádraig Brady
Subject: Re: Speed parameter for 'dd' command
Date: Fri, 18 Dec 2009 14:31:54 +0000
User-agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.5) Gecko/20091204 Thunderbird/3.0

On 18/12/09 14:11, sdrb wrote:
You mean - have I tried to use ionice with IDLE class?
Yes, I tried ionice with IDLE parameter, but if I have to run more than
one "dd" simultaneously - even if I use IDLE class - I have not any
influence on this how the IDLE class will share I/O resources into those
dd commands.

My intention was to limit the I/O operations to given value - so it
could be possible to do I/O at this speed or a bit slower but not faster
that the set value. It doesn't have to keep given average I/O speed for
the whole time with 1 byte accuracy.

In the simplest version it could be done by sleeping for some time after
transmitting one block of data for as long as the average I/O data speed
is equal to set one with "speed" parameter. This "speed" parameter could
be optional - not obligatory.

I've made some patch for doing this and it works quite good. It allows
to keep very low load average, but of course the whole "dd" process
takes much more time to finish.

I don't think this belongs in dd.
Have you tried `rsync --bwlimit` or `pv -L` ?

cheers,
Pádraig.




reply via email to

[Prev in Thread] Current Thread [Next in Thread]