process priority

[Kevin Buettner]

On Jul 18,  2:00am, shock wrote:

>    I understand how to change a processes priority while 
> it is running with renice. What I would like to know is
> how to start an application at a higher priority. 
>    For instance, if I wanted to run mpg123 with a higher
> priority, how would I do it? I could script it, but 
> is there another way?
>    Any suggestions on where to look? I've read through
> all of the man pages that I could find on processes.
> nice, renice, setpriority...

You need to use ``nice'' to start a process at a different priority. 
Since you've read the ``nice'' man page, you know that process
priorities range from -20 which is the highest priority to 19 which is
the lowest.

What may not have been clear from the man page is that the superuser
may specify a negative increment to ``nice'' which will result in the
process being run at a higher priority.  Ordinary users can only
specify positive increments, however, which result in running the
process at a lower priority.

You may want to play around with running mpg123 via ``nice'' as root
to see if it helps.  My guess is that you won't see much difference in
performance.  (But do report back to the list if it does help; I'd be
interested in hearing about your experience.)  Something which may or
may not help more is to play around with the different scheduling
algorithms available in the linux kernel.  These are selectable when
you configure the kernel.

Kevin