HP-UX Reference (11i v1 05/09) - 1M System Administration Commands A-M (vol 3)

k
kmtune(1M) kmtune(1M)
Default: default value from master file
Minimum: minimum
Module: module
Version: version
Dynamic: Yes/No
If the -l option is specified without the
-q query option, a detailed report on all the parameters is
displayed. The information between the parameters is separated by blank lines.
If the parameter has no minimum value specified in a master file, minimum will be displayed as
-’. If the
parameter is not supplied by kernel modules, module will be displayed as
-’. In the brief listing the
module and version fields are blank unless the parameter comes from a dynamically loadable kernel
module.
The Current field is an integer read from the running kernel. Some parameters are not stored in the run-
ning kernel and are displayed as
-
’. The Value string is a copy of the default value or what is stored in a
system file.
The Dynamic field, in the
-l output, is either Yes or No,
and indicates whether the parameter can be
changed using
-u. This avoids rebuilding and rebooting. In the brief listing Y is used to indicate dynamic
parameters.
If the -s set option is specified with an equal (=) separator and the minimum value of the parameter is
described in a master file, the value range is checked. If the minimum value or the specified value is a for-
mula, the check is not made. More restrictive range checking may be done by the kernel whenever
-u is
used.
If the
-s set option with a plus (+) separator is specified and the original value is non numeric, an error is
reported.
NOTES
System administrators are encouraged to use
kmsystem and kmtune instead of editing description files
manually. File format of description files are subject to change, and
kmtune is intended to provide compa-
tibility in case of format change.
The -u option is new functionality that allows changes to values in the kernel that have always been con-
stant before. Programs using pstat(), getrlimit() ,orsysconf()
may have been written with
the previously correct assumption that the returned variables do not vary while the system is running. The
use of
kmtune to modify the running kernel may cause such programs to produce erroneous results or
even abort.
When lowering system limits, processes that exceed the new limit will be "grandfathered". Such processes
may not be able to reallocate a resource that had just been released and may fail in ways that were very
unlikely before. After lowering maxfiles , a process may be in violation of the new limit. If it closes a
file and then reopens it, the open may fail. See settune(2).
RETURN VALUE
Upon completion, kmtune returns with one of the following exit values:
0 Successful.
1 Requested parameter is not found, the value is out of range, or the type of value is formula.
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 messages are sent to stderr.
EXAMPLES
# kmtune -q shmseg
Parameter Current Dyn Planned Module Version
========================================================
shmseg 120 Y 120
# kmtune -s shmseg=155
# kmtune -l -q shmseg
Section 1M408 Hewlett-Packard Company 2 HP-UX 11i Version 1: September 2005