diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/lib/utils/os_utils.h | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/src/lib/utils/os_utils.h b/src/lib/utils/os_utils.h index 590ed4ae7..c8cd599d0 100644 --- a/src/lib/utils/os_utils.h +++ b/src/lib/utils/os_utils.h @@ -20,11 +20,17 @@ namespace OS { uint32_t get_process_id(); /** +* Return the highest resolution clock available on the system. +* +* The epoch and update rate of this clock is arbitrary and depending +* on the hardware it may not tick at a constant rate. +* * Returns the value of the hardware cycle counter, if available. -* Returns 0 if not available. On Windows uses QueryPerformanceCounter. -* On other platforms reads the native cycle counter directly. -* The epoch and update rate are arbitrary and may not be constant -* (depending on the hardware). +* On Windows calls QueryPerformanceCounter. +* Under GCC or Clang on supported platforms the hardware cycle counter is queried: +* x86, PPC, Alpha, SPARC, IA-64, S/390x, and HP-PA +* On other platforms clock_gettime is used with some monotonic timer, if available. +* As a final callback std::chrono::high_resolution_clock is used. */ uint64_t get_processor_timestamp(); |