$slot = 1;

my $pm = new Parallel::ForkManager( 2 );

foreach $key ( sort { lc $a cmp lc $b || $a cmp $b } keys %array ) {
	if( $slot == 2 ){ $slot = 1; } elsif( $slot == 1 ){ $slot = 2; }
	$pm->start and next;
	if( ! -e "/mnt/storage/videotemp/$key.hevc" ) {
		$cmd = 'WINEPREFIX=~/.wine64_'.$slot.' wine ... ;
		print "\n$cmd\n\n";
		exec($cmd);
	}
	$pm->finish;
}

$pm->wait_all_children;