For a Microsoft Win2K system admin class, I've written a trivial script to help the students practice performance monitoring. The script loops forever alternating a few seconds of massive CPU use with a few seconds of idleness.

However, I’m afraid I’m making it too easy for the students

Is there a way for me to precisely suck CPU? I'd like to suck say 20% of CPU for a few seconds, then suck 85% for a few more seconds, then suck 95% for a few more seconds, etc...

I didn’t find any CPU monitoring modules on CPAN.

#!/usr/bin -w

# script to drive cpu use to max for a specific period

use strict;

our $now_sec;
our $end_sec;

our $busy_period=4;
our $sleep_period=4;

our $n1;
our $n2;
our $n3;
our $n4;

print "Press control - C or use task manager to kill me";
while (1) {
    ($end_sec)=$now_sec+$busy_period;


    $n1=$n2=$n3=$n4=3.14;
    
    while($now_sec<$end_sec){
        $n1=$n2=$n3=$n4=$n1*$n2*$n3*$n4;
        ($now_sec)=localtime(time);
    }
    sleep($sleep_period);

}

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In reply to gulpng CPU with precision by mandog

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