NAME
Parallel::Scoreboard - a scoreboard for monitoring status of many
workers
SYNOPSIS
use Parallel::Scoreboard;
my $scoreboard = Parallel::Scoreboard->new(
base_dir => '/tmp/my_scoreboard'
...
# in each worker process
$scoreboard->update('this is my current status');
# to read status of all worker processes
my $stats = $scoreboard->read_all();
for my $pid (sort { $a <=> $b } keys %$stats) {
print "status for pid:$pid is: ", $stats->{$pid}, "\n";
}
DESCRIPTION
Parallel::Scoreboard is a pure-perl implementation of a process
scoreboard. By using the module it is easy to create a monitor for many
worker process, like the status module of the Apache HTTP server.
Unlike other similar modules, Parallel::Scoreboard is easy to use and
has no limitation on the format or the length of the statuses to be
stored. Any arbitrary data (like JSON or frozen perl object) can be
saved by the worker processes as their status and read from the manager
process.
METHODS
new(%args)
instantiation. Recognizes the following paramaters. The parameters can
be read using the read-only accessors with the same name.
base_dir => $base_dir
the directory name in which the scoreboard files will be stored. The
directory will be created if it does not exist already. Mandatory
parameter.
worker_id => sub { ... }
a subref that returns the id of the worker (if omitted, the module uses
$$ (process id) to distinguish between the workers)
update($status)
saves the status of the process
read_all()
reads the status of all worker processes that are alive and that have
called update() more than once. Returned value is a hashref with process
ids as keys and the statuses of each processes as corresponding values.
cleanup()
remove obsolete status files found in base_dir. The files are normally
removed upon the termination of worker process, however they might be
left unremoved if the worker process was killed for some reason. The
detection and removal of the obsolete status files is performed by
read_all() as well.
SEE ALSO
IPC::ScoreBoard Proc::Scoreboard
AUTHOR
Kazuho Oku <kazuhooku gmail.com>
LICENSE
This program is free software, you can redistribute it and/or modify it
under the same terms as Perl 5.10.
