Clarify FreeBSD instructions in pg_test_timing.

Josh Kupershmidt
This commit is contained in:
Bruce Momjian 2012-08-30 18:38:00 -04:00
parent b5dc7612a5
commit c36b06a70d
1 changed files with 8 additions and 3 deletions

View File

@ -183,8 +183,13 @@ Histogram of timing durations:
information about the timer selected during boot:
<screen>
dmesg | grep "Timecounter"
sysctl kern.timecounter.hardware=TSC
# dmesg | grep "Timecounter"
Timecounter "ACPI-fast" frequency 3579545 Hz quality 900
Timecounter "i8254" frequency 1193182 Hz quality 0
Timecounters tick every 10.000 msec
Timecounter "TSC" frequency 2531787134 Hz quality 800
# sysctl kern.timecounter.hardware=TSC
kern.timecounter.hardware: ACPI-fast -> TSC
</screen>
</para>
@ -277,7 +282,7 @@ Histogram of timing durations:
</para>
<para>
Timers used on older PC hardware including the 8254 Programmable Interval
Timers used on older PC hardware include the 8254 Programmable Interval
Timer (PIT), the real-time clock (RTC), the Advanced Programmable Interrupt
Controller (APIC) timer, and the Cyclone timer. These timers aim for
millisecond resolution.