kernel/tools/perf/Documentation/perf-stat.txt, branch linux-3.11.y

perf stat: Add per-core aggregation

2013-03-25T19:13:26Z

This patch adds the --per-core option to perf stat. This option is used to aggregate system-wide counts on a per physical core basis. On processors with hyperthreading, this means counts of all HT threads running on a physical core are aggregated. This mode is useful to find imblance between physical cores running an uniform workload. Cores are identified by socket: S0-C1, means physical core 1 on socket 0. Note that cores are identified using their physical core id, thus their numbering may not be continuous. Per core aggregation can be combined with interval printing: # perf stat -a --per-core -I 1000 -e cycles sleep 1000 # time core cpus counts events 1.000090030 S0-C0 1 4,765,747 cycles 1.000090030 S0-C1 1 5,580,647 cycles 1.000090030 S0-C2 1 221,181 cycles 1.000090030 S0-C3 1 266,092 cycles Signed-off-by: Stephane Eranian Cc: Andi Kleen Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1360846649-6411-4-git-send-email-eranian@google.com [ committer note: Remove parts already applied on 86ee6e1 to keep bisectability ] Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Rename --aggr-socket to --per-socket

2013-03-25T19:09:24Z

To make it more obvious what this option does as suggested by Andi on LKML. Signed-off-by: Stephane Eranian Cc: Andi Kleen Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1360846649-6411-3-git-send-email-eranian@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Introduce --repeat forever

2013-03-15T17:01:26Z

The following patch causes 'perf stat --repeat 0' to be interpreted as 'forever', displaying the stats for every run. We act as if a single run was asked, and reset the stats in each iteration. In this mode SIGINT is passed to perf to be able to stop the loop with Ctrl+C. Signed-off-by: Frederik Deweerdt Cc: Ingo Molnar Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20130301180227.GA24385@ks398093.ip-192-95-24.net Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add per processor socket count aggregation

2013-02-06T21:09:27Z

This patch adds per-processor socket count aggregation for system-wide mode measurements. This is a useful mode to detect imbalance between sockets. To enable this mode, use --aggr-socket in addition to -a. (system-wide). The output includes the socket number and the number of online processors on that socket. This is useful to gauge the amount of aggregation. # ./perf stat -I 1000 -a --aggr-socket -e cycles sleep 2 # time socket cpus counts events 1.000097680 S0 4 5,788,785 cycles 2.000379943 S0 4 27,361,546 cycles 2.001167808 S0 4 818,275 cycles Signed-off-by: Stephane Eranian Cc: Andi Kleen Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1360161962-9675-3-git-send-email-eranian@google.com [ committer note: Added missing man page entry based on above comments ] Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add interval printing

2013-01-30T13:36:53Z

This patch adds a new printing mode for perf stat. It allows interval printing. That means perf stat can now print event deltas at regular time interval. This is useful to detect phases in programs. The -I option enables interval printing. It expects an interval duration in milliseconds. Minimum is 100ms. Once, activated perf stat prints events deltas since last printout. All modes are supported. $ perf stat -I 1000 -e cycles noploop 10 noploop for 10 seconds # time counts events 1.000109853 2,388,560,546 cycles 2.000262846 2,393,332,358 cycles 3.000354131 2,393,176,537 cycles 4.000439503 2,393,203,790 cycles 5.000527075 2,393,167,675 cycles 6.000609052 2,393,203,670 cycles 7.000691082 2,393,175,678 cycles The output format makes it easy to feed into a plotting program such as gnuplot when the -I option is used in combination with the -x option: $ perf stat -x, -I 1000 -e cycles noploop 10 noploop for 10 seconds 1.000084113,2378775498,cycles 2.000245798,2391056897,cycles 3.000354445,2392089414,cycles 4.000459115,2390936603,cycles 5.000565341,2392108173,cycles Signed-off-by: Stephane Eranian Cc: Andi Kleen Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1359460064-3060-3-git-send-email-eranian@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add --pre and --post command

2012-10-26T13:22:25Z

In order to measure kernel builds, one has to do some pre/post cleanup work in order to do the repeat build. So provide --pre and --post command hooks to allow doing just that. perf stat --repeat 10 --null --sync --pre 'make -s O=defconfig-build/clean' \ -- make -s -j64 O=defconfig-build/ bzImage Signed-off-by: Peter Zijlstra Acked-by: Ingo Molnar Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1350992414.13456.5.camel@twins [ committer note: Added respective entries in Documentation/perf-stat.txt ] Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Allow multiple threads or processes in record, stat, top

2012-02-14T00:54:11Z

Allow a user to collect events for multiple threads or processes using a comma separated list. e.g., collect data on a VM and its vhost thread: perf top -p 21483,21485 perf stat -p 21483,21485 -ddd perf record -p 21483,21485 or monitoring vcpu threads perf top -t 21488,21489 perf stat -t 21488,21489 -ddd perf record -t 21488,21489 Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1328718772-16688-1-git-send-email-dsahern@gmail.com Signed-off-by: David Ahern Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add --log-fd option to redirect stderr elsewhere

2011-09-29T20:03:23Z

This perf stat option emulates valgrind's --log-fd option, allowing the user to send perf results elsewhere, and leaving stderr for use by the program under test. This complements --output file option, and is mutually exclusive with it. 3>results perf stat --log-fd 3 -- $cmd 3>>results perf stat --log-fd 3 --append -- $cmd The perl distro's make test.valgrind target uses valgrind's --log-fd option, I've adapted it to invoke perf also, and tested this patch there. Link: http://lkml.kernel.org/r/1315437244-3788-2-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Jim Cromie Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add -o and --append options

2011-08-18T10:46:13Z

This patch adds an option (-o) to save the output of perf stat into a file. You could do this with perf record but not with perf stat. Instead, you had to fiddle with stderr to save the counts into a separate file. The patch also adds the --append option so that results can be concatenated into a single file across runs. Each run of the tool is clearly separated by a comment line starting with a hash mark. The -A option of perf record is already used by perf stat, so we only add a long option. $ perf stat -o res.txt date $ cat res.txt Performance counter stats for 'date': 0.791306 task-clock # 0.668 CPUs utilized 2 context-switches # 0.003 M/sec 0 CPU-migrations # 0.000 M/sec 197 page-faults # 0.249 M/sec 1878143 cycles # 2.373 GHz stalled-cycles-frontend stalled-cycles-backend 1083367 instructions # 0.58 insns per cycle 193027 branches # 243.935 M/sec 9014 branch-misses # 4.67% of all branches 0.001184746 seconds time elapsed The option can be combined with -x to make the output file much easier to parse. Cc: Ingo Molnar Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20110815202233.GA18535@quad Signed-off-by: Stephane Eranian Signed-off-by: Arnaldo Carvalho de Melo

perf tool: Add cgroup support

2011-02-16T12:30:48Z

This patch adds the ability to filter monitoring based on container groups (cgroups) for both perf stat and perf record. It is possible to monitor multiple cgroup in parallel. There is one cgroup per event. The cgroups to monitor are passed via a new -G option followed by a comma separated list of cgroup names. The cgroup filesystem has to be mounted. Given a cgroup name, the perf tool finds the corresponding directory in the cgroup filesystem and opens it. It then passes that file descriptor to the kernel. Example: $ perf stat -B -a -e cycles:u,cycles:u,cycles:u -G test1,,test2 -- sleep 1 Performance counter stats for 'sleep 1': 2,368,667,414 cycles test1 2,369,661,459 cycles cycles test2 1.001856890 seconds time elapsed Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra LKML-Reference: <4d590290.825bdf0a.7d0a.4890@mx.google.com> Signed-off-by: Ingo Molnar