README
1NAME
2 Parallel::Scoreboard - a scoreboard for monitoring status of many
3 workers
4
5SYNOPSIS
6 use Parallel::Scoreboard;
7
8 my $scoreboard = Parallel::Scoreboard->new(
9 base_dir => '/tmp/my_scoreboard'
10 ...
11
12 # in each worker process
13 $scoreboard->update('this is my current status');
14
15 # to read status of all worker processes
16 my $stats = $scoreboard->read_all();
17 for my $pid (sort { $a <=> $b } keys %$stats) {
18 print "status for pid:$pid is: ", $stats->{$pid}, "\n";
19 }
20
21DESCRIPTION
22 Parallel::Scoreboard is a pure-perl implementation of a process
23 scoreboard. By using the module it is easy to create a monitor for many
24 worker process, like the status module of the Apache HTTP server.
25
26 Unlike other similar modules, Parallel::Scoreboard is easy to use and
27 has no limitation on the format or the length of the statuses to be
28 stored. Any arbitrary data (like JSON or frozen perl object) can be
29 saved by the worker processes as their status and read from the manager
30 process.
31
32METHODS
33 new(%args)
34 instantiation. Recognizes the following paramaters. The parameters can
35 be read using the read-only accessors with the same name.
36
37 base_dir => $base_dir
38 the directory name in which the scoreboard files will be stored. The
39 directory will be created if it does not exist already. Mandatory
40 parameter.
41
42 worker_id => sub { ... }
43 a subref that returns the id of the worker (if omitted, the module uses
44 $$ (process id) to distinguish between the workers)
45
46 update($status)
47 saves the status of the process
48
49 read_all()
50 reads the status of all worker processes that are alive and that have
51 called update() more than once. Returned value is a hashref with process
52 ids as keys and the statuses of each processes as corresponding values.
53
54 cleanup()
55 remove obsolete status files found in base_dir. The files are normally
56 removed upon the termination of worker process, however they might be
57 left unremoved if the worker process was killed for some reason. The
58 detection and removal of the obsolete status files is performed by
59 read_all() as well.
60
61SEE ALSO
62 IPC::ScoreBoard Proc::Scoreboard
63
64AUTHOR
65 Kazuho Oku <kazuhooku gmail.com>
66
67LICENSE
68 This program is free software, you can redistribute it and/or modify it
69 under the same terms as Perl 5.10.
70
71