a process supervisor in Perl
Latest commit 5fe1ce8 Aug 26, 2013 @yannk Add lock preventing unintentional rerun of cfkd
Note: it's possible to launch two cfkd, but they have to specify
different home directory.

Closes #15


What is ControlFreak?

  see also: - lib/ControlFreak/Tutorial.pod
            - lib/ControlFreak.pm (pod)

ControlFreak's intent is to help you really control your (web) app (in
production and in development) and your resources effectively.

It's a process supervisor:

- It fixes the mess of pid file management
- It facilitates the roll-forward and backward of releases
- It optionally controls the resources that your app needs
  (essentially sockets) and make these resources available to your app using
  a push model
- ... and many other benefits like flexible logging/monitoring of everything

It supervises any type of services. Examples:

In Dev:
- memcached
- gearmand
- perlbal
- plack
- workers
- ddlockd

In Prod:
- gearman workers
- schwartz workers
- plack (web) workers)
- (or, apache if you prefer)

How does it work?

It is a pure Perl implementation consisting in:
- a controlling process: cfkd, which runs an AnyEvent loop usually running
  in the background
- a command line tool to talk to it: cfkctl
- a configuration file (just a bunch of commands really)

cfkd forks to start (exec) the services it controls.

Optimally, cfkd binds sockets and share them with workers before forking
(known as pre-fork module), it can also make you benefit from Copy On Write
effect (sharing memory between all your workers for instance).

At your command cfkd, restarts, stops, kills any service.