multithreading - Perl 有多处理模块吗？

Question

Perl 有多处理模块吗？与 Python 的multiprocessing 模块提供的功能相似的东西。

我知道我可以使用 Perl 构建类似的功能，但我正在寻找已经实现的东西。

Answer 1

forks提供与线程相同的出色接口，但使用进程而不是线程。

use forks;  # Or: use threads;
use Thread::Queue;

my $q = Thread::Queue->new();

my @workers;
for (1..NUM_WORKERS) {
   push @workers, async {
      while (defined(my $job = $q->dequeue())) {
         ...
      }
   };
}

$q->enqueue(...);

$q->enqueue(undef) for @workers;
$_->join for @workers;

---

将分叉与 Forks::Super 进行比较。

请记住，这些假设是 Forks::Super 擅长的情况！

use Forks::Super;
sub do_something { my @args = @_; ... }
$process = fork { sub => \&do_something, args => [@args] };
$process->wait;

可以写成

use forks;
sub do_something { my @args = @_; ... }
$process = async { do_something(@args) };
$process->join;

---

use Forks::Super;
my $x = 42;
my @y = ();
my %z = ();
sub do_something_else {
    $x = 19;
    @y = qw(foo bar);
    %z = (foo => 'bar');
}
$process = fork { sub => 'do_something_else', share => [\$x, \@y, \%z ] };
$process->wait;

可以写成

use forks;
use forks::shared;
my $x :shared = 42;
my @y :shared = ();
my %z :shared = ();
sub do_something_else {
    $x = 19;
    @y = qw(foo bar);
    %z = (foo => 'bar');
}
$process = async { do_something_else() };
$process->join;

---

use Forks::Super;
use IO::Handle;
pipe my $child_read, my $parent_write;
pipe my $parent_read, my $child_write;
$parent_write->autoflush(1);
$child_write->autoflush(1);
sub square {
    while (my $x = <$child_read>) {
        chomp($x);
        print {$child_write} $x ** 2, "\n";
    }
    close $child_write;
}
$process = fork { sub => 'square' };
print { $parent_write } "9\n";
chomp( my $result = <$parent_read> );  # 81
close $parent_write;
$process->wait;

可以写成

use forks;
use Threads::Queue;
my $req = Threads::Queue->new();
my $resp = Threads::Queue->new();
sub square { $_[0] ** 2 }
$process = async {
    while (defined(my $x = $req->dequeue())) {
        $resp->enqueue( square($x) );
    }
};
$req->enqueue(9);
my $result = $resp->dequeue();  # 81
$resp->enqueue(undef);
$process->join;

---

use Forks::Super;
sub square_root {
    sleep 1 && seek STDIN,0,1 while eof(STDIN); # ok, this is a workaround for an existing bug :-(
    while (my $x = <STDIN>) {
        chomp($x);
        print sqrt($x), "\n";
    }
}
$process = fork { sub => 'square_root', child_fh => 'in,out,block' };
$process->write_stdin("81\n");
chomp( $result = $process->read_stdout() );  # 9
$process->close_fh('stdin');
$process->wait;

可以写成

use forks;
use Threads::Queue;
my $req = Threads::Queue->new();
my $resp = Threads::Queue->new();
$process = async {
    while (defined(my $x = $req->dequeue())) {
        $resp->enqueue( sqrt($x) );
    }
};
$req->enqueue(81);
my $result = $resp->dequeue();  # 9
$resp->enqueue(undef);
$process->join;

Answer 2

我认为Forks::Super非常接近。它有一些功能可以在后台进程中运行任意子程序（或外部命令），监视后台进程并发出信号，并使进程间通信不那么痛苦。

use Forks::Super;

sub do_something { my @args = @_; ... }
$process = fork { sub => \&do_something, args => [@args] };
$process->wait;


my $x = 42;
my @y = ();
my %z = ();
sub do_something_else {
    $x = 19;
    @y = qw(foo bar);
    %z = (foo => 'bar');
}
$process = fork { sub => 'do_something_else', share => [\$x, \@y, \%z ] };
$process->wait;
# $x, @y, and %z are now updated with changes made in background process


# create your own pipes to use for IPC
use IO::Handle;
pipe my $child_read, my $parent_write;
pipe my $parent_read, my $child_write;
$parent_write->autoflush(1);
$child_write->autoflush(1);
sub square {
    while (my $x = <$child_read>) {
        print {$child_write} $x ** 2, "\n";
    }
    close $child_write;
}
$process = fork { sub => 'square' };
print {$parent_write} "9\n";
my $result = <$parent_read>;    # should be "81\n";
close $parent_write;

# or use the standard I/O handles for IPC
sub square_root {
    sleep 1 && seek STDIN,0,1 while eof(STDIN); # ok, this is a workaround for an existing bug :-(
    while (my $x = <STDIN>) {
        print sqrt($x), "\n";
    }
}
$process = fork { sub => 'square_root', child_fh => 'in,out,block' };
$process->write_stdin("81\n");
$result = $process->read_stdout(); #  =>  "9\n"

这两个multiprocessing模块Forks::Super都具有很多功能。你对哪些特别感兴趣？

我是这本书的作者，Forks::Super我的目标是包含任何人们认为有用的并行处理特性，所以如果multiprocessing你想要 Perl 中的某个特性，请告诉我。

Answer 3

POE：Perl 对象环境怎么样？它支持异步子进程。

Answer 4

你可以使用https://github.com/marioroy/mce-perl 它类似于 python 多进程模块