NAME

pmccontrol —

control hardware performance monitoring counters

SYNOPSIS

pmccontrol [-c cpu | -d pmc | -e pmc] ...

pmccontrol -l

pmccontrol -L

pmccontrol -s

DESCRIPTION

The pmccontrol utility controls the operation of the system's hardware performance monitoring counters.

OPTIONS

The pmccontrol utility processes options in command line order, so later options modify the effect of earlier ones. The following options are available:

-c cpu: Subsequent enable and disable options affect the CPU denoted by argument cpu. The argument cpu is a number denoting a CPU in the system, or “*”, denoting all unhalted CPUs in the system.
-d pmc: Disable PMC number pmc on the CPU specified by -c, preventing it from being used till subsequently re-enabled. The argument pmc is a number denoting a specific PMC, or “*” denoting all the PMCs on the specified CPU.
Only idle PMCs may be disabled.
-e pmc: Enable PMC number pmc, on the CPU specified by -c, allowing it to be used in the future. The argument pmc is a number denoting a specific PMC, or “*” denoting all the PMCs on the specified CPU. If PMC pmc is already enabled, this option has no effect.
-l: List available hardware performance counters and their current disposition.
-L: List available hardware performance counter classes and their supported event names.
-s: Print driver statistics maintained by hwpmc(4).

EXAMPLES

To disable all PMCs on all CPUs, use the command:

pmccontrol -d*

To enable all PMCs on all CPUs, use:

pmccontrol -e*

To disable PMCs 0 and 1 on CPU 2, use:

pmccontrol -c2 -d0 -d1

To disable PMC 0 of CPU 0 only, and enable all other PMCS on all other CPUs, use:

pmccontrol -c* -e* -c0
  -d0

DIAGNOSTICS

The pmccontrol utility exits 0 on success, and >0 if an error occurs.

HISTORY

The pmccontrol utility first appeared in FreeBSD 6.0.

AUTHORS

Joseph Koshy <jkoshy@FreeBSD.org>