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authorLen Brown <len.brown@intel.com>2012-09-21 23:45:46 -0400
committerLen Brown <len.brown@intel.com>2012-09-26 18:17:21 -0400
commit2f32edf12c1eafc8e5b1b0337360993fde1b3565 (patch)
tree4064b83fc867a2fb1d745590fddfc323f66c19d1 /tools/power/x86/turbostat/turbostat.8
parent130ff304f6d31484fc73bb337bc635cba1ffe04c (diff)
tools/power turbostat: add [-m MSR#] option
-m MSR# prints the specified MSR in 32-bit format -M MSR# prints the specified MSR in 64-bit format Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'tools/power/x86/turbostat/turbostat.8')
-rw-r--r--tools/power/x86/turbostat/turbostat.814
1 files changed, 13 insertions, 1 deletions
diff --git a/tools/power/x86/turbostat/turbostat.8 b/tools/power/x86/turbostat/turbostat.8
index 74e44507dfe..8e7b29af78f 100644
--- a/tools/power/x86/turbostat/turbostat.8
+++ b/tools/power/x86/turbostat/turbostat.8
@@ -6,12 +6,14 @@ turbostat \- Report processor frequency and idle statistics
.B turbostat
.RB [ "\-s" ]
.RB [ "\-v" ]
+.RB [ "\-m MSR#" ]
.RB [ "\-M MSR#" ]
.RB command
.br
.B turbostat
.RB [ "\-s" ]
.RB [ "\-v" ]
+.RB [ "\-m MSR#" ]
.RB [ "\-M MSR#" ]
.RB [ "\-i interval_sec" ]
.SH DESCRIPTION
@@ -35,7 +37,10 @@ The \fB-p\fP option limits output to the 1st thread in each package.
.PP
The \fB-v\fP option increases verbosity.
.PP
-The \fB-M MSR#\fP option dumps the specified MSR,
+The \fB-m MSR#\fP option dumps the specified 32-bit MSR,
+in addition to the usual frequency and idle statistics.
+.PP
+The \fB-M MSR#\fP option dumps the specified 64-bit MSR,
in addition to the usual frequency and idle statistics.
.PP
The \fB-i interval_sec\fP option prints statistics every \fiinterval_sec\fP seconds.
@@ -165,6 +170,13 @@ may work poorly on Linux-2.6.20 through 2.6.29,
as \fBacpi-cpufreq \fPperiodically cleared the APERF and MPERF
in those kernels.
+If the TSC column does not make sense, then
+the other numbers will also make no sense.
+Turbostat is lightweight, and its data collection is not atomic.
+These issues are usually caused by an extremely short measurement
+interval (much less than 1 second), or system activity that prevents
+turbostat from being able to run on all CPUS to quickly collect data.
+
The APERF, MPERF MSRs are defined to count non-halted cycles.
Although it is not guaranteed by the architecture, turbostat assumes
that they count at TSC rate, which is true on all processors tested to date.