NAME

IPC::ConcurrencyLimit::Lock::NFS - Locking via NFS

SYNOPSIS

  use IPC::ConcurrencyLimit;

DESCRIPTION

This locking strategy uses File::SharedNFSLock to implement locking on NFS shares across multiple hosts. The locking technique employed by File::SharedNFSLock should work on other, local file systems as well. If in doubt, do your own testing.

Beware: If processes are killed harshly without being able to clean up, stale lock files may remain that are not recoverable. In principle, File::SharedNFSLock can reclaim them after a timeout, but that feature does not seem to make a lot of sense in this context. All File::SharedNFSLock gotchas apply.

METHODS

new

Given a hash ref with options, attempts to obtain a lock in the pool. On success, returns the lock object, otherwise undef.

Required options:

path

The directory that will hold the lock files. Created if it does not exist. It is suggested not to use a directory that may hold other data.

max_procs

The maximum no. of locks (and thus usually processes) to allow at one time.

lock_file

Returns the full path and name of the lock file.

path

Returns the directory in which the lock files resides.

AUTHOR

Steffen Mueller, smueller@cpan.org

COPYRIGHT AND LICENSE

 (C) 2011 Steffen Mueller. All rights reserved.
 
 This code is available under the same license as Perl version
 5.8.1 or higher.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.