use Parallel::ForkManager;
use Shell;

my @list = glob("*.fasta");

my $pm = new Parallel::ForkManager(10);

foreach my $list (@list) {

    my $pid = $pm->start and next;
    my $base = ( split( /\./, $list) )[0];
    system("perl mycode.pl $base > ~/MyPerl/result_ans/$base.out");

    $pm->finish; # Terminates the child process

}