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kmtune(1M)							    kmtune(1M)

       kmtune -	query, set, or reset system parameters

       name]...] system_file]


       namevalue]...] name]...]
	      comment] system_file]


       is  used	 to  query,  set,  or  reset  system parameters.  displays the
       planned values of all system parameters when used without  any  options
       or with the or option.  reads traditional and modular kernel configura-
       tion files.  See	config(1M), master(4) and system(4).  It also  gathers
       information on the running kernel using the system call.

       Unless the option is specified, changes do not take effect immediately.
       Changes to system parameters not	associated with	 dynamically  loadable
       kernel modules do not take effect until the kernel has been rebuilt and
       the system has been rebooted.  Changes to  parameters  associated  with
       dynamically loadable kernel modules do not take effect until the	module
       is re-configured	and registered with  the  running  kernel.   See  con-
       fig(1M) and kmupdate(1M).

       The following options are recognized by

       Specify an optional comment string.  All	changes	to the
	    kernel  parameters are logged with the date, old value, new	value,
	    user id and	this comment.  This option is used with	and  The  com-
	    ment  text	will  generally	need to	be quoted so that it is	inter-
	    preted as a	single parameter by the	shell.	The comment  text  may
	    contain  newlines.	 The  log is written to	the file The format of
	    the	log file is subject to change in the future.

       Print a brief difference	report.	 Only parameters where the
	    planned and	current	values	are  different	are  listed.   If  the
	    planned  value  is	a formula, it is NOT considered	different from
	    the	current	value.	This option is useful to insure	that only  de-
	    sired  changes  will be made on a subsequent invocation of The op-
	    tion cannot	be used	with the or options.

       Evaluate	the expression given by	"value".  The expression
	    is anything	allowed	in the option.	The output will	always	be  in

       Print a detailed	report.
	    The	option cannot be used with the or options.

       Query the value of the specified	system parameter.

       Reset the value of the specified	system parameter to the	default.

       Set the value of	the specified system parameter.	If the separator is an
       equal sign
	    the	parameter is set to the	value specified.  If the separator  is
	    a  plus  sign the parameter	is incremented by the value specified.
	    Negative values cannot be used with	plus sign The namevalue	format
	    must not include spaces or tabs.

       Specify	the  HP-UX  system  description	 file name (traditional	system
       file).  If not specified,
	    is used as the default.

       Update the currently running kernel.  This modifies the
	    and	options, to update the running kernel as well  as  the	system
	    files.   The  values specified must	be numeric.  The whole command
	    will fail if any non dynamic parameters are	being  set.   The  and
	    options  are  processed in the order they are listed.  When	incre-
	    menting a value with the option the	kernel and  the	 system	 files
	    are	set to the value in the	system file plus the increment value.

	    When  used alone, or with it updates all the dynamic parameters to
	    match the numeric values stored in the system files.  A warning is
	    reported if	any static parameters have differences.	 The order the
	    parameters are listed in the system	files is not  important.   The
	    option  can	be used	to look	at the differences to get a preview of
	    what a lone	will do.

	    Use	of requires super user privileges.

       If the query option is specified, displays the following	format:

       Brief report without option

       Detailed	report with option

       If the option is	specified without the query option, a detailed	report
       on all the parameters is	displayed.  The	information between the	param-
       eters is	separated by blank lines.

       Any values not returned by the kernel or	read from a master file,  will
       be displayed as (dash).

       In  the brief report, the Module	field is blank unless the parameter is
       associated with a packaged module.  See config(1M).   In	 the  detailed
       report,	the  Module field is unless the	parameter is associated	with a
       packaged	module.

       The Current field is an integer read  from  the	running	 kernel.   The
       Planned field contains the value	last set with the (or options.	It may
       be a formula, or	a literal.  The	Value field  is	 an  integer  computed
       from the	Pending	string.	 This value is what the	parameter would	be set
       to if were run.	Formulas are evaluated using the Value	field  of  any
       other parameters	used in	the formula.

       The  Dynamic field, in the output, is either "Yes" or "No."  Parameters
       that are	dynamic	can be changed without rebooting.  Changing other  pa-
       rameters	requires rebooting.  In	the brief listing "Y" is used to indi-
       cate dynamic parameters.

       If the set option is specified and the minimum or maximum value of  the
       parameter  is  returned	by the kernel or described in its master file,
       the value range is checked.  If the  minimum  and  maximum  values  are
       printed as a dash in the	long listing then no range check is made.

       The  expressions	used with the options are built	of literal values, the
       upper case names	of other kernel	parameters, and	the  following	opera-
       tors:  the unary	operators and the binary operators and and the ternary

       Using to	create a circular dependency in	the values of the  kernel  pa-
       rameters	is not allowed.

       System  administrators  must use	kmsystem(1M) and kmtune(1M) instead of
       editing files manually.	The format of kernel  configuration  files  is
       subject	to change, and is intended to provide compatibility in case of
       format change.  See config(1M), master(4) and system(4).

       Changing	kernel parameters dynamically is a fairly new  feature.	  Pro-
       grams using pstat(2), getrlimit(2), or sysconf(2) may have been written
       with the	previously correct assumption that the returned	values do  not
       vary  while  the	 system	 is running.  The use of to modify the running
       kernel may cause	such programs to produce  erroneous  results  or  even

       Some dynamic kernel parameters can be raised dynamically, but cannot be
       lowered without rebuilding the kernel and rebooting.  See the man pages
       for those parameters for	details.

       When dynamically	lowering per-process limits, processes that exceed the
       new limit will be "grandfathered".  Such	processes will retain the  old
       limit.	The old	limit will also	apply to any child processes they cre-
       ate after the change.  Some parameters have exceptions to this  general
       policy; see the man pages for those parameters for details.

       It  is  possible	to put multiple	and options on a single	command.  will
       try to make all of the changes, in the order listed.  If	an  error  oc-
       curs with one of	the changes, the state of the other changes is not de-

       Upon completion,	returns	with one of the	following exit values:

	      0	     Successful.

	      1	     Requested parameter is not	found, the  value  is  out  of
		     range, or the format of the value is not valid.

	      2	     Syntax error.

	      3	     Changes  in  static  parameters were found	when trying to
		     dynamically update	the running kernel.

	      >3     Environmental error.

       Results of query	requests are sent to stdout.  Error and	 warning  mes-
       sages are sent to stderr.

       Traditional and modular master configuration files

       Default HP-UX system description	file (traditional system file)

       Modular system files

       Log of all tunable changes made using

       config(1M),  kmsystem(1M),  settune(2),	tuneinfo2(2),  master(4), sys-
       tem(4), and the individual tunable parameter man	pages in section 5.



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