#!/usr/bin/perl
my $logfile   = '/var/log/top';
my $max_size  = 10**6;
my $max_files = 10;
my $delay     = 2;
my $count     = 0;
my $num       = 0; 
    
while (1) {
    my $time = scalar localtime;
    # rotate logfiles so they don't get too big
    if ( -e "$logfile$num.log" and -s "$logfile$num.log" > $max_size ) {
        $count++;
        $num = $count % $max_files;
        unlink "$logfile$num.log" if -e "$logfile$num.log";
    }
    my $top = `top -n1`;
    open LOG, ">>$logfile$num.log" or die "Can't write $logfile $!\n";
    print LOG $time, "\n", $top, "\n\n";
    close LOG;
    sleep $delay;
}