open(PID, "/proc/$$/statm");
return (split(' ', <PID>))[5] * 4;

##</code><code>##

my $handling = 0;
sub DB::sub {
    return &$DB::sub if $handling;
    $handling = 1;
    scalar $Q->dequeue if $Q->pending > $OPTS{ LINES };
    $Q->enqueue( $DB::sub );
    $handling = 0;
    return &$DB::sub;
}