[ltp] Duty Cycle program

Jeffrey Taylor linux-thinkpad@linux-thinkpad.org
Sat, 22 Dec 2007 17:15:45 -0600


Quoting Jeffrey Taylor <linux-tp@austinblues.dyndns.org>:
> Quoting Henrique de Moraes Holschuh <hmh@hmh.eng.br>:
> > On Thu, 20 Dec 2007, Jeffrey Taylor wrote:
[snip]
> > But you might find out that running the CPU in ondemand mode, letting it go
> > into C3 as often as possible ends up keeping it coller than lowering the
> > maximum frequency.  If that happens, there's nothing you can do, short of
> > writing something that sends the "STOP" signal and "CONT" signal to the
> > processes you want to control the duty-cycle of.
> > 
> 
> This is a promising lead.  I have the programming skills to write this, and
> modify find to handle STOP and CONT signals if it doesn't already.  It is easy
> enough to test out.  For big program builds, I could do the same thing to make
> (letting a compile run full speed to completion is probably acceptable if make
> runs in bursts).
> 

This works for find at least.  I can start the find command in the background
and stop and restart it with "killall -STOP find" and "killall -CONT find".
If I was willing to use really coarse time slices, I could do it in a shell
script.  I'll dig further and see if this is OS or program behavior, or just
default handlers for STOP and CONT signals.

Thank you,
  Jeffrey