pmc.tsc3
Measurements using the i386 timestamp counter
Usage
#include <pmc.h>
Library
library “libpmc”
Overview
In the i386 architecture, the timestamp counter is a monotonically non-decreasing counter that counts processor cycles.
This counter may be selected specifying an event specifier “tsc” to pmc_allocate(3). The TSC is a read-only counter that may only be allocated in system-wide counting mode. The “tsc” event does not support further event qualifiers.
Multiple processes are allowed to allocate the TSC. Once allocated, the TSC may be read using the pmc_read() function, or by using the RDTSC instruction.
Event Name Aliases
The alias “cycles” maps to the TSC.
Releases
41 releases since FreeBSD 7.3-RELEASE; the text changed 30 times.