Re: Loadavg calculation

[Pavel Machek <pavel@suse.cz>]

Hi!

> > I'm working a project a work that is using Linux to run some very
> > math-intensive calculations.   One of the things we do is use the 1-minute
> > loadavg to determine how busy the machine is and can we fire off another
> > program to do more calculations.    However, there's a problem with that.
> > 
> > Because it's a 1 minute load average, there's quite a bit of lag time from
> > when 1 program finishes until the loadavg goes down below a threshold for
> > our control mechanism to fire off another program.
> > 
> > Let me give an example (all on a 1-cpu PC)
> > 
> > HH:MM:SS
> > 00:00:00    		fire off 4 programs 
> > 00:01:00		loadavg goes up to 4
> > 00:01:30		3 of the 4 programs finish loadavg still at 4
> > 00:02:20		load avg goes down to 1, below our threshold
> > 00:02:21		we fire off 3 more programs.
> > 
> > We'd like to reduce that almost 50 second lag time.  Is it possible, in
> > user-space, to duplicate the loadavg calculation period, say to a 15
> > second load average, using the information in /proc?

pavel@bug:~$ cat /proc/loadavg
0.00 0.00 0.00 2/46 395
pavel@bug:~$

The three values of 0.00 are loadavg averaged over different
time. Select the right one and you are done.
								Pavel
-- 
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org
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