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Net::Server::PreFork(3U)ser
NAME
  Net::Server::PreFork - Net::Server personality

SYNOPSIS
    use Net::Server::PreFork;
    @ISA = qw(Net::Server::PreFork);

    sub process_request {
       #...code...
    }

    __PACKAGE__->run();

DESCRIPTION
  Please read the pod on Net::Server and Net::Server::PreForkSimple first.
  This module is a personality, or extension, or sub class, of the
  Net::Server::PreForkSimple class which is a sub class of Net::Server.	 See
  Net::Server::PreForkSimple.

  This personality binds to one or more ports and then forks "min_servers"
  child process.  The server will make sure that at any given time there are
  "min_spare_servers" available to receive a client request, up to
  "max_servers".  Each of these children will process up to "max_requests"
  client connections.  This type is good for a heavily hit site, and should
  scale well for most applications.  (Multi port accept is accomplished using
  flock to serialize the children).

SAMPLE CODE
  Please see the sample listed in Net::Server.

COMMAND LINE ARGUMENTS
  In addition to the command line arguments of the Net::Server base class and
  the Net::Server::PreForkSimple parent class, Net::Server::PreFork contains
  several other configurable parameters.  You really should also see
  Net::Server::PreForkSimple.

    Key			Value			Default
    min_servers		\d+			5
    min_spare_servers	\d+			2
    max_spare_servers	\d+			10
    max_servers		\d+			50
    max_requests	\d+			1000

    serialize		(flock|semaphore|pipe)	undef
    # serialize defaults to flock on multi_port or on Solaris
    lock_file		"filename"		POSIX::tmpnam

    check_for_dead	\d+			30
    check_for_waiting	\d+			10

    max_dequeue		\d+			undef
    check_for_dequeue	\d+			undef

    child_communication 1			undef

  min_servers
      The minimum number of servers to keep running.

  min_spare_servers
      The minimum number of servers to have waiting for requests.  Minimum
      and maximum numbers should not be set to close to each other or the
      server will fork and kill children too often.

  max_spare_servers
      The maximum number of servers to have waiting for requests.  See
      min_spare_servers.

  max_servers
      The maximum number of child servers to start.  This does not apply to
      dequeue processes.

  check_for_waiting
      Seconds to wait before checking to see if we can kill off some waiting
      servers.

  child_communication
      Enable child communication to parent via unix sockets.  If set to true,
      will let children write to the socket contained in
      $self->{server}->{parent_sock}.  The parent will be notified through
      child_is_talking_hook where the first argument is the socket to the
      child.  The child's socket is stored in
      $self->{server}->{children}->{$child_pid}->{sock}.

CONFIGURATION FILE
  "Net::Server::PreFork" allows for the use of a configuration file to read
  in server parameters.	 The format of this conf file is simple key value
  pairs.  Comments and white space are ignored.

    #-------------- file test.conf --------------

    ### server information
    min_servers	  20
    max_servers	  80
    min_spare_servers 10
    min_spare_servers 15

    max_requests  1000

    ### user and group to become
    user	somebody
    group	everybody

    ### logging ?
    log_file	/var/log/server.log
    log_level	3
    pid_file	/tmp/server.pid

    ### access control
    allow	.+\.(net|com)
    allow	domain\.com
    deny	a.+

    ### background the process?
    background	1

    ### ports to bind
    host	127.0.0.1
    port	localhost:20204
    port	20205

    ### reverse lookups ?
    # reverse_lookups on

    ### enable child communication ?
    # child_communication

    #-------------- file test.conf --------------

PROCESS FLOW
  Process flow follows Net::Server until the loop phase.  At this point
  "min_servers" are forked and wait for connections.  When a child accepts a
  connection, finishs processing a client, or exits, it relays that
  information to the parent, which keeps track and makes sure there are
  enough children to fulfill "min_servers", "min_spare_servers",
  "max_spare_servers", and "max_servers".

HOOKS
  The PreFork server has the following hooks in addition to the hooks
  provided by PreForkSimple.  See Net::Server::PreForkSimple.

  "$self->run_n_children_hook()"
      This hook occurs at the top of run_n_children which is called each time
      the server goes to start more child processes.  This gives the parent
      to do a little of its own accountting (as desired).  Idea for this hook
      came from James FitzGibbon.

  "$self->parent_read_hook()"
      This hook occurs any time that the parent reads information from the
      child.  The line from the child is sent as an argument.

  "$self->child_is_talking_hook()"
      This hook occurs if child_communication is true and the child has
      written to $self->{server}->{parent_sock}.  The first argument will be
      the open socket to the child.

TO DO
  See Net::Server

AUTHOR
  Paul T. Seamons paul@seamons.com

THANKS
  See Net::Server

SEE ALSO
  Please see also Net::Server::Fork, Net::Server::INET,
  Net::Server::PreForkSimple, Net::Server::MultiType, Net::Server::Single
  Net::Server::SIG Net::Server::Daemonize Net::Server::Proto

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