tail head cat sleep
QR code linking to this page

Manual Pages  — KGMON


kgmon – generate a dump of the operating system's profile buffers



kgmon [-Bbhpr] [-M core] [-N system]


The kgmon utility is used when profiling the operating system. When no arguments are supplied, kgmon indicates the state of operating system profiling as running, off, or not configured. (see config(8)) If the -p flag is specified, kgmon extracts profile data from the operating system and produces a gmon.out file suitable for later analysis by gprof(1).

The options are as follows:
  Resume the collection of high resolution profile data.
  Resume the collection of low resolution profile data.
  Stop the collection of profile data.
  Dump the contents of the profile buffers into a gmon.out file.
  Reset all the profile buffers. If the -p flag is also specified, the gmon.out file is generated before the buffers are reset.
  Extract values associated with the name list from the specified core instead of the default /dev/kmem.
  Extract the name list from the specified system instead of the default /boot/kernel/kernel.

If neither -B nor -b nor -h is specified, the state of profiling collection remains unchanged. For example, if the -p flag is specified and profile data is being collected, profiling will be momentarily suspended, the operating system profile buffers will be dumped, and profiling will be immediately resumed.

The profile buffers should be reset when the resolution of the profile data is changed.


  the default system
/dev/kmem the default memory


Users with only read permission on /dev/kmem cannot change the state of profiling collection. They can get a gmon.out file with the warning that the data may be inconsistent if profiling is in progress.


gprof(1), config(8), pmcstat(8)


The kgmon utility appeared in BSD 4.2 .

KGMON (8) November 27, 2017

tail head cat sleep
QR code linking to this page

Please direct any comments about this manual page service to Ben Bullock. Privacy policy.

Like a classics radio station whose play list spans decades, Unix simultaneously exhibits its mixed and dated heritage. There's Clash-era graphics interfaces; Beatles-era two-letter command names; and systems programs (for example, ps) whose terse and obscure output was designed for slow teletypes; Bing Crosby-era command editing (# and @ are still the default line editing commands), and Scott Joplin-era core dumps.
— The Unix Haters' handbook