Re: Support for SIGSTOP/SIGCONT in nice?

[Jim Meyering]

Simon Josefsson <address@hidden> wrote:
...
> Frequently when I want to run a long-running I/O-bound job (i.e.,
> rsync of the entire disk to a second disk) on a busy machine (i.e.,
> mail and web server), the load increases to ~10 from a normal <1.
> Using 'nice' doesn't help.  I don't know why this is, but I suspect
> the kernel scheduler is sub-optimal for disk-bound jobs.
>
> Would it be useful to consider extending nice so it can send SIGSTOP
> and SIGCONT signals in configurable intervals?  Having rsync run for
> 30 seconds, sleep for 15, run for 30 seconds, etc, seem to avoid
> slowing down the system to unusable levels.

Hi Simon,

Have you already tried using rsync's existing option to limit bandwidth?

  rsync --bwlimit=500 ...