Why the array? can't you just pipe it and read one line at a time?

#script.pl
$|++;

my $i = 0;
while (1) {
     $i++;
     print $i % 50000 == 0 ? "Event" : "stuff\n";
}


#monitor.pl

while (<STDIN>) {
     if (/Event/) {
          notify();
     }
}

sub notify {
     print "Got notification.\n";
}





$ ./script.pl | ./monitor.pl
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