BMC/Intel-BMC/linux.git/tools/perf/Documentation/perf-stat.txt, branch dev

perf stat: Introduce --per-thread option

2015-06-26T15:05:04+00:00

Currently all the -p option PID arguments tasks values get aggregated and printed as single values. Adding --per-tasks option to print values per task. $ perf stat -e cycles,instructions --per-thread -p 30190,30242 ^C Performance counter stats for process id '30190,30242': cat-30190 0 cycles yes-30242 3,842,525,421 cycles cat-30190 0 instructions yes-30242 10,370,817,010 instructions 1.143155657 seconds time elapsed Also works under interval mode: $ perf stat -e cycles,instructions --per-thread -p 30190,30242 -I 1000 # time comm-pid counts unit events 1.000073435 cat-30190 89,058 cycles 1.000073435 yes-30242 3,360,786,902 cycles (100.00%) 1.000073435 cat-30190 14,066 instructions 1.000073435 yes-30242 9,069,937,462 instructions 2.000204830 cat-30190 0 cycles 2.000204830 yes-30242 3,351,667,626 cycles 2.000204830 cat-30190 0 instructions 2.000204830 yes-30242 9,045,796,885 instructions ^C 2.771286639 cat-30190 0 cycles 2.771286639 yes-30242 2,593,884,166 cycles 2.771286639 cat-30190 0 instructions 2.771286639 yes-30242 7,001,171,191 instructions It works only with -t and -p options, otherwise following error is printed: $ perf stat -e cycles --per-thread -I 1000 ls The --per-thread option is only available when monitoring via -p -t options. -p, --pid stat events on existing process id -t, --tid stat events on existing thread id Signed-off-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Andi Kleen Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1435310967-14570-23-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Document parameterized and symbolic events

2015-01-21T16:24:33+00:00

Signed-off-by: Cody P Schafer Signed-off-by: Sukadev Bhattiprolu Acked-by: Jiri Olsa Cc: Cody P Schafer Cc: Haren Myneni Cc: Jiri Olsa Cc: Michael Ellerman Cc: Paul Mackerras Cc: Peter Zijlstra Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/1420679633-28856-5-git-send-email-sukadev@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fix --delay option in man page

2014-01-13T13:06:24+00:00

The --delay option was documented as --initial-delay in the manpage. Fix this. Signed-off-by: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/1389132847-31982-1-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo

tools/perf/stat: Add perf stat --transaction

2013-10-04T08:06:07+00:00

Add support to perf stat to print the basic transactional execution statistics: Total cycles, Cycles in Transaction, Cycles in aborted transsactions using the in_tx and in_tx_checkpoint qualifiers. Transaction Starts and Elision Starts, to compute the average transaction length. This is a reasonable overview over the success of the transactions. Also support architectures that have a transaction aborted cycles counter like POWER8. Since that is awkward to handle in the kernel abstract handle both cases here. Enable with a new --transaction / -T option. This requires measuring these events in a group, since they depend on each other. This is implemented by using TM sysfs events exported by the kernel Signed-off-by: Andi Kleen Acked-by: Arnaldo Carvalho de Melo Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1377128846-977-5-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar

perf stat: Add support for --initial-delay option

2013-08-07T20:35:29+00:00

When measuring workloads the startup phase -- doing page faults, dynamic linking, opening files -- is often very different from the rest of the workload. Especially with smaller kernels and using counter multiplexing this can give significant measurement errors. Multiplexing assumes that the workload is mostly the same over longer periods. But at startup there is typically some spike of activity which is relatively short. If many groups are multiplexing the one group seeing the spike, and which is then scaled up over the time to run all groups, may see a significant error. Also in general it's often not useful to measure the startup, because it is so different from the rest. One way around this is to use interval mode and discard the first sample, but this can be awkward because interval mode doesn't support intervals of less than 100ms, and also a useful interval is not necessarily the same as a useful startup delay. This patch adds a new --initial-delay / -D option to skip measuring for the startup phase. The time can be specified in ms Here's a simple example: perf stat -e page-faults bash -c 'for i in $(seq 100000) ; do true ; done' ... 3,721 page-faults ... If we just wait 20 ms the number of page faults is 1/3 less: perf stat -D 20 -e page-faults bash -c 'for i in $(seq 100000) ; do true ; done' ... 2,823 page-faults ... So we filtered out most of the startup noise from bash. Signed-off-by: Andi Kleen Reviewed-by: Jiri Olsa Cc: Jiri Olsa Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1375490473-1503-4-git-send-email-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add per-core aggregation

2013-03-25T19:13:26+00:00

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

2013-03-25T19:09:24+00:00

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

2013-03-15T17:01:26+00:00

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

2013-02-06T21:09:27+00:00

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

2013-01-30T13:36:53+00:00

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