$ cat swaphogger.pl
#!/usr/bin/perl -w

use strict;

sub start_hogging_memory  {
        my @blackhole;
        my $count = 0;
        print __FILE__ . " [" . __LINE__ . "] child [$$]\n";
        open ( FH, "> ${0}_${$}.output" ) or die " could not open file:$!\n";
        my $swapon = `swapon -s | tail -1`;
        while ( 1 ) { 
                chomp( $swapon );
                print FH "[$swapon $count]\n"; 
                push @blackhole, "$count -----------------------------------------------------------------------\n"; 
                $count++;
                $swapon = `swapon -s | tail -1` # strangeness
        }
        close (FH);
}

my $maxChildren = shift;
my $numChildren = 0;

while ( $numChildren < $maxChildren ) {
        $numChildren++;
        my $pid = fork();
        if ( $pid == 0 ) {
                start_hogging_memory ();
        } elsif ( $pid ) {
                print __FILE__ . " [" . __LINE__ . "] parent [$$]\n";
        } else {
                die __FILE__ . " [" . __LINE__ . "] couldn't fork() :$!\n";
        }
}