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Diffstat (limited to 'tools/perf/Documentation/perf-stat.txt')
-rw-r--r-- | tools/perf/Documentation/perf-stat.txt | 56 |
1 files changed, 45 insertions, 11 deletions
diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt index e6c3b4e555c2..5dfe102fb5b5 100644 --- a/tools/perf/Documentation/perf-stat.txt +++ b/tools/perf/Documentation/perf-stat.txt @@ -116,6 +116,22 @@ Do not aggregate counts across all monitored CPUs. print counts using a CSV-style output to make it easy to import directly into spreadsheets. Columns are separated by the string specified in SEP. +--table:: Display time for each run (-r option), in a table format, e.g.: + + $ perf stat --null -r 5 --table perf bench sched pipe + + Performance counter stats for 'perf bench sched pipe' (5 runs): + + # Table of individual measurements: + 5.189 (-0.293) # + 5.189 (-0.294) # + 5.186 (-0.296) # + 5.663 (+0.181) ## + 6.186 (+0.703) #### + + # Final result: + 5.483 +- 0.198 seconds time elapsed ( +- 3.62% ) + -G name:: --cgroup name:: monitor only in the container (cgroup) called "name". This option is available only @@ -294,20 +310,38 @@ Users who wants to get the actual value can apply --no-metric-only. EXAMPLES -------- -$ perf stat -- make -j +$ perf stat -- make + + Performance counter stats for 'make': + + 83723.452481 task-clock:u (msec) # 1.004 CPUs utilized + 0 context-switches:u # 0.000 K/sec + 0 cpu-migrations:u # 0.000 K/sec + 3,228,188 page-faults:u # 0.039 M/sec + 229,570,665,834 cycles:u # 2.742 GHz + 313,163,853,778 instructions:u # 1.36 insn per cycle + 69,704,684,856 branches:u # 832.559 M/sec + 2,078,861,393 branch-misses:u # 2.98% of all branches + + 83.409183620 seconds time elapsed + + 74.684747000 seconds user + 8.739217000 seconds sys + +TIMINGS +------- +As displayed in the example above we can display 3 types of timings. +We always display the time the counters were enabled/alive: + + 83.409183620 seconds time elapsed - Performance counter stats for 'make -j': +For workload sessions we also display time the workloads spent in +user/system lands: - 8117.370256 task clock ticks # 11.281 CPU utilization factor - 678 context switches # 0.000 M/sec - 133 CPU migrations # 0.000 M/sec - 235724 pagefaults # 0.029 M/sec - 24821162526 CPU cycles # 3057.784 M/sec - 18687303457 instructions # 2302.138 M/sec - 172158895 cache references # 21.209 M/sec - 27075259 cache misses # 3.335 M/sec + 74.684747000 seconds user + 8.739217000 seconds sys - Wall-clock time elapsed: 719.554352 msecs +Those times are the very same as displayed by the 'time' tool. CSV FORMAT ---------- |