unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (OSF1-V5.1-alpha)
Page:
Section:
Apropos / Subsearch:
optional field



psm.h(4)							     psm.h(4)



NAME

  psm.h	- Header file for the PSM vital	process	monitoring subsystem

SYNOPSIS

    #ifndef _PSM_H_
    #define _PSM_H_

    #include <&lt;ksm/ksm.h>&gt;

DESCRIPTION

  The Process Set Manager (PSM)	is a loadable kernel subsystem that monitors
  the state of vital processes.	   The PSM is layered the Kernel Set Manager
  (KSM), and uses the Category and MIB-id relationships	it provides.

  PSM uses the Event Manager (EVM) to generate events that are available for
  subscription by other	system entities	and users. For	example, PSM gen-
  erates an event when processes are started or	when they exit.	This feature
  is described in EVM Events.

  PSM Process Categories and Members


  Processes monitored by PSM are organized as follows:

    +  Process Category	- You create a process category	by using the
       cfg_psm_catops()	function. Refer	to cfg_psm_catops(3) for information.

    +  Process Category	Member - Each process to be monitored is registered
       as a member of a	category. You create a member by using the
       cfg_psm_memops()	function. Refer	to cfg_psm_memops(3) for information.

  For each process, PSM	maintains the following	data which is described	in
  detail in cfg_psm_memops(3).

    +  A cluster-wide unique name specifying the cluster node number

    +  Its process identifier (PID)

    +  Its termination status, only valid when the process exit	flag is	set

    +  Its flag	settings

    +  A user-modifiable state string which has	two predefined values: run-
       ning and	exited

    +  Its saved argument vector, only complete	if the argv-truncation flag
       is not set

  Monitoring of	processes by PSM is subject to the following rules:

    +  After a process exits, termination status continues to be available
       until either the	process	is restarted or	you manually remove it.

    +  When a process is restarted, any	exited process instance	in the target
       category	is replaced by the new instance	of the process.

    +  A specific process instance is registered in only one category.

  EVM Events


  When you use PSM, the	following EVM events are generated and become avail-
  able for subscription	at the local node. Events are always posted in the
  order	that they occur:

    +  sys.unix.psm.set.create - This event is available for subscription at
       the local host when you create a	PSM set.

    +  sys.unix.psm.set.remove - This event is available for subscription at
       the local host when you remove a	PSM set.

    +  sys.unix.psm.category.create - This event is available for subscrip-
       tion at the host	containing the category	name when you create a
       category. (See RESTRICTIONS.)

    +  sys.unix.psm.category.remove - This event is available for subscrip-
       tion at the host	containing the category	name when you remove a
       category.

    +  sys.unix.psm.instance.create - This event is available for subscrip-
       tion cluster-wide when you create a process instance. The event data
       contains	the category name and the PID.

    +  sys.unix.psm.instance.remove - This event is available for subscrip-
       tion cluster-wide when you remove a running instance. The event data
       contains	the category name and the PID.

    +  sys.unix.psm.instance.exited - This event is available for subscrip-
       tion cluster-wide when a	process	instance exits.	 The event data	con-
       tains the category name,	its PID, and its termination status.

  See EVM(5) for information on	how to retrieve	these events. See
  sys_attrs_psm(5) for information on tuning and configuring PSM subsystem
  attrributes.

RESTRICTIONS

  The Kernel Set Manager (KSM) does not	permit set removal. Once the PSM
  module is loaded, it cannot be unloaded.

  The KSM does not permit category removal.

ERRORS

  If an	attribute supports a range (-N to +N) any attempt to exceed the	max-
  imum or minimum value	returns	an ENOSPC subsystem error.

  Any attempt to re-register a currently running process causes	an EALREADY
  subsystem error.

  Any attempt to remove	a category returns an ENOTSUP subsystem	error.






FILES

  /usr/sys/include/ksm/psm/psm.h
      Location of the header file.


SEE ALSO

  Commands: sysconfig(8), sysconfigdb(8)

  Library: cfg_psm_catops(3), cfg_psm_memops(3), libcfg(3)

  Misc:	EVM(5),	sys_attrs_psm(5)