1Parallel::Pipes(3pm)  User Contributed Perl Documentation Parallel::Pipes(3pm)
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NAME

6       Parallel::Pipes - parallel processing using pipe(2) for communication
7       and synchronization
8

SYNOPSIS

10         use Parallel::Pipes;
11
12         my $pipes = Parallel::Pipes->new(5, sub {
13           # this is a worker code
14           my $task = shift;
15           my $result = do_work($task);
16           return $result;
17         });
18
19         my $queue = Your::TaskQueue->new;
20         # wrap Your::TaskQueue->get
21         my $get; $get = sub {
22           my $queue = shift;
23           if (my @task = $queue->get) {
24             return @task;
25           }
26           if (my @written = $pipes->is_written) {
27             my @ready = $pipes->is_ready(@written);
28             $queue->register($_->read) for @ready;
29             return $queue->$get;
30           } else {
31             return;
32           }
33         };
34
35         while (my @task = $queue->$get) {
36           my @ready = $pipes->is_ready;
37           $queue->register($_->read) for grep $_->is_written, @ready;
38           my $min = List::Util::min($#task, $#ready);
39           for my $i (0..$min) {
40             # write tasks to pipes which are ready
41             $ready[$i]->write($task[$i]);
42           }
43         }
44
45         $pipes->close;
46

DESCRIPTION

48       THIS IS EXPERIMENTAL.
49
50       Parallel processing is essential, but it is also difficult:
51
52       How can we synchronize our workers?
53           More precisely, how to detect our workers are ready or finished.
54
55       How can we communicate with our workers?
56           More precisely, how to collect results of tasks.
57
58       Parallel::Pipes tries to solve these problems with pipe(2) and
59       select(2).
60
61       App::cpm, a fast CPAN module installer, uses Parallel::Pipes.  Please
62       look at App::cpm
63       <https://github.com/skaji/cpm/blob/master/lib/App/cpm.pm> or eg
64       directory <https://github.com/skaji/Parallel-Pipes/tree/master/eg> for
65       real world usages.
66

METHOD

68   new
69         my $pipes = Parallel::Pipes->new($number, $code);
70
71       The constructor, which takes
72
73       number
74           The number of workers.
75
76       code
77           Worker's code.
78
79   is_ready
80         my @ready = $pipes->is_ready;
81         my @ready = $pipes->is_ready(@pipes);
82
83       Get pipes which are ready to write.
84
85   is_written
86         my @written = $pipes->is_written;
87
88       Get pipes which are written.
89
90   close
91         $pipes->close;
92
93       Close pipes (also shutdown workers).
94

AUTHOR

96       Shoichi Kaji <skaji@cpan.org>
97

99       Copyright 2016 Shoichi Kaji <skaji@cpan.org>
100
101       This library is free software; you can redistribute it and/or modify it
102       under the same terms as Perl itself.
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106perl v5.34.0                      2021-07-22              Parallel::Pipes(3pm)
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