perl Parallel :: ForkManager卡在這個腳本中？

Question

我想並行運行一個Perl腳本，並在這裏卡住了一個點。查看示例腳本：

如果我沒有-fork 4選項來運行它，它運行良好：

perl perl_parallel_forkmanager_ls.pl -limit 10              
799c89a4c78eafbfb9e7962b8e9705f7 /etc/apt/trusted.gpg 
ff163e8e9e38670705a9f2cea8b530c9 /etc/apt/trusted.gpg~ 
075e92fd5c6f0dcdad857603f03dd3a5 /etc/bash_completion.d/R 
b269c1383a87a7da2cc309c929ba35ca /etc/bash_completion.d/grub 
7cbefff45508d2ed69576bebc80e66bb /etc/bash_completion.d/docker 
facb1fdc0fcf7f6b150442d1a9036795 /etc/bash_completion.d/pulseaudio-bash-completion.sh 
69dfca7a7b55181cef06b9ed28debb20 /etc/gnome/defaults.list 
a65e81e55558941ce0f3080b9333e18f /etc/sensors3.conf 
9e87bc86a77261acfb2bae618073a787 /etc/grub.d/20_linux_xen 
8039709ee9648dabda0cdca713f2ed49 /etc/grub.d/30_os-prober 
1bc18861cc2438517ce6b6c22fd4fa49 /etc/grub.d/10_linux 

但是，如果我的-fork 4比-limit 10值小的值運行它，它忽略了價值的限制：

perl perl_parallel_forkmanager_ls.pl -fork 4 -limit 10 2>/dev/null | wc -l 
80 

任何想法？

#!/usr/bin/perl 
use strict; 
use warnings; 
use Parallel::ForkManager; 
use Getopt::Long; 
my $dir = '/etc'; my $fork = 1; my $size = '9876'; my $limit; 
my $verbose; 
GetOptions(
     'dir:s' => \$dir, 
      'fork:s' => \$fork, 
      'size:s' => \$size, 
      'limit:s' => \$limit, 
     'verbose' => \$verbose, 
     ); 
my $cmd; my $ret; 
$cmd = "find $dir -size +".$size."c -type f 2>/dev/null"; 
open(P, "-|", "$cmd") or die "$cmd -- $!"; 
my $pm; $pm=new Parallel::ForkManager($fork) if ($fork > 1); 
my $count = 0; 
while (<P>) { 
    if ($fork > 1) { 
    $pm->start and next; 
    } 
    my $file = $_; chomp $file; 
    my $md5 = `md5sum $file`; 
    print "$md5"; 
    $pm->finish if ($fork > 1); 
    $count++; 
    last if (defined $limit && $count > $limit); 
}; 
$pm->wait_all_children if ($fork > 1); 
close P; 

Answer 1

$pm->finish後的聲明從來沒有達到時，給出-fork > 1。您應該改變while循環語句的順序：

while (<P>) { 
    $count++; 
    last if (defined $limit && $count > $limit); 
    if ($fork > 1) { 
     $pm->start and next; 
    } 
    my $file = $_; chomp $file; 
    my $md5 = `md5sum $file`; 
    print "$md5"; 
    $pm->finish if ($fork > 1); 
};