The London Perl and Raku Workshop takes place on 26th Oct 2024. If your company depends on Perl, please consider sponsoring and/or attending.

NAME

SHARYANTO::Proc::Daemon::Prefork - Create preforking, autoreloading daemon

VERSION

version 0.29

METHODS

new(%args)

Arguments:

  • require_root => BOOL (default 0)

    If true, bails out if not running as root.

  • error_log_path (required if daemonize=1)

  • access_log_path => STR (required if daemonize=1)

  • pid_path => STR (required if daemonize=1)

  • scoreboard_path => STR (default none)

    If not set, no scoreboard file will be created/updated. Scoreboard file is used to communicate between parent and child processes. Autoadjustment of number of processes, for example, requires this (see max_children for more details).

  • daemonize => BOOL (default 1)

  • prefork => INT (default 3, 0 means a nonforking/single-threaded daemon)

    This is like the StartServers setting in Apache webserver (the prefork MPM), the number of children processes to prefork.

  • max_children => INT (default 150)

    This is like the MaxClients setting in Apache webserver. Initially the number of children spawned will follow the 'prefork' setting. If while serving requests, all children are busy, parent will automatically increase the number of children gradually until 'max_children'. If afterwards these children are idle, they will be gradually killed off until there are 'prefork' number of children again.

    Note that for this to function, scoreboard_path must be defined since the parent needs to communicate with children.

  • auto_reload_check_every => INT (default undef, meaning never)

    In seconds.

  • auto_reload_handler => CODEREF (required if auto_reload_check_every is set)

  • after_init => CODEREF (default none)

    Run after the daemon initializes itself (daemonizes, writes PID file, etc), before spawning children. You usually bind to sockets here (if your daemon is a network server).

  • on_client_disconnect => CODEREF

    Do something after socket connection between client and child process is closed. This requires scoreboard (see scoreboard_path argument) to record all the children's PIDs, and also the "netstat" command and Parse::Netstat module to check for connections.

    This can be used, for example, to kill child process (cancel job) on disconnect.

    Will be called for each child server being disconnected. Code will receive a hash containing: pid, proto, local_host, local_port, foreign_host, foreign_port.

    Note that monitoring connections is done every few seconds by the parent process, so this code will not be run immediately after closing of connection.

    Currently only works for TCP connections and not Unix connections, due to lack of information provided by "netstat" for Unix connections.

  • main_loop* => CODEREF

    Run at the beginning of each child process. This is the main loop for your daemon. You usually do this in your main loop routine:

     for(my $i=1; $i<=$MAX_REQUESTS_PER_CHILD; $i++) {
         # accept loop, or process job loop
     }
  • before_shutdown => CODEREF (optional)

    Run before killing children and shutting down.

DESCRIPTION

This module has Rinci metadata.

FUNCTIONS

None are exported by default, but they are exportable.

AUTHOR

Steven Haryanto <stevenharyanto@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2012 by Steven Haryanto.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.