NAME

       x2gobroker-loadchecker - Load checker service for X2Go Session Broker

SYNOPSIS

       x2gobroker-loadchecker [ options ]

DESCRIPTION

       x2gobroker-loadchecker  is  a  service  that  collects  system  load  metrics from broker-
       associated X2Go Servers.

       When load-balancing shall be used, the simplest way to detect "server  load"  is  counting
       the numbers of running and suspended sessions. No extra daemon nor service is required for
       this. The server with the least amount of sessions will be selected for starting the  next
       X2Go session.

       However,   simply   counting   running  and  suspended  sessions  per  X2Go  Server  as  a
       representative for the server load can be highly inaccurate. A better approach is checking
       each X2Go Server's load in regular intervals by the x2gobroker-loadchecker daemon (running
       on the broker host) and querying the x2gobroker-loadchecker daemon  before  selecting  the
       best server on session startup requests.

       The  x2gobroker-loadchecker  collects  server  metrics  of all associated X2Go Servers and
       keeps the latest load factors in RAM. Once the broker needs  load  factors  of  a  certain
       session profile (i.e., of all servers configured in that session profile), the x2gobroker-
       loadchecker delivers that info immediately. The remembered load factors may  not  be  100%
       up-to-date (default: collected within the last five minutes), but the response time of the
       load checker is much faster than a query to all possible X2Go Servers would be.

       The load factor calculation uses this algorithm:

                       ( memAvail[MByte]/1000 ) * numCPUs * typeCPUs[MHz]
         load-factor = --------------------------------------------------
                                  loadavg*100 * numSessions

       The higher the load-factor, the more likely that a server will be chosen for the  next  to
       be allocated X2Go session.

       The  communication  between  X2Go  Session  Broker and the Load Checker Service is handled
       through a unix domain socket file (<RUNDIR>/x2gobroker/x2gobroker-loadchecker.socket).

       This command is normally started through the host's init system.

COMMON OPTIONS

       x2gobroker-loadchecker accepts the following common options:

       -h, --help
              Display a help with all available command line options and exit.

       -D, --daemonize
              Fork this application to background and detach from the running terminal.

       -P, --pidfile
              Custom PID file location when daemonizing (default: <RUNDIR>/x2gobroker/x2gobroker-
              loadchecker.pid).

       -L, --logdir
              Directory  where stdout/stderr will be redirected after having daemonized (default:
              /var/log/x2gobroker/).

       -s <LOADCHECKERSOCKET>, --socket <LOADCHECKERSOCKET>
              File name of the unix domain socket file used for communication between broker  and
              load checker service.

       -o <OWNER>, --owner <OWNER>
              User ownership of the <LOADCHECKERSOCKET> file.

       -g <GROUP>, --group <GROUP>
              Group ownership of the <LOADCHECKERSOCKET> file.

       -p <PERMISSIONS>, --permissions <PERMISSIONS>
              Set  these  file  permissions  for  the  <LOADCHECKERSOCKET>  file.  Use  numerical
              permissions (e.g. 0640).

FILES

       <RUNDIR>/x2gobroker/x2gobroker-loadchecker.socket

AUTHOR

       This manual has been written for the  X2Go  project  by  Mike  Gabriel  <mike.gabriel@das-
       netzwerkteam.de>.