理解并发数关键的概念

pmprepare.pl

#!/usr/bin/perl

#zinc have 91G mols
#we should convert mols to pdbqts
#author: chenzhaoqiang
#date: 2015-01-20


use strict;
use warnings;
use Parallel::Runner;

my @zincs=<ZINC*mol2>; #
my $runner = Parallel::Runner->new(20);  #设置并发数，会自动等待完成的，这才是多线程的思想，
my $command;
foreach my $mol(@zincs)
{
   $runner->run(
   sub{
       $command="prepare_ligand4.py -l $mol";  #这里涉及到如果给闭包传递参数
       system($command);
   }
 );        

}
$runner->finish;