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Diffstat (limited to 'tools/perf/Documentation/perf-record.txt')
| -rw-r--r-- | tools/perf/Documentation/perf-record.txt | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index b3f3b3f1c161..fa8a5fcd27ab 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -458,7 +458,9 @@ This option sets the time out limit. The default value is 500 ms. --switch-events:: Record context switch events i.e. events of type PERF_RECORD_SWITCH or -PERF_RECORD_SWITCH_CPU_WIDE. +PERF_RECORD_SWITCH_CPU_WIDE. In some cases (e.g. Intel PT or CoreSight) +switch events will be enabled automatically, which can be suppressed by +by the option --no-switch-events. --clang-path=PATH:: Path to clang binary to use for compiling BPF scriptlets. @@ -556,6 +558,19 @@ overhead. You can still switch them on with: --switch-output --no-no-buildid --no-no-buildid-cache +--switch-output-event:: +Events that will cause the switch of the perf.data file, auto-selecting +--switch-output=signal, the results are similar as internally the side band +thread will also send a SIGUSR2 to the main one. + +Uses the same syntax as --event, it will just not be recorded, serving only to +switch the perf.data file as soon as the --switch-output event is processed by +a separate sideband thread. + +This sideband thread is also used to other purposes, like processing the +PERF_RECORD_BPF_EVENT records as they happen, asking the kernel for extra BPF +information, etc. + --switch-max-files=N:: When rotating perf.data with --switch-output, only keep N files. @@ -596,6 +611,21 @@ Make a copy of /proc/kcore and place it into a directory with the perf data file Limit the sample data max size, <size> is expected to be a number with appended unit character - B/K/M/G +--num-thread-synthesize:: + The number of threads to run when synthesizing events for existing processes. + By default, the number of threads equals 1. + +ifdef::HAVE_LIBPFM[] +--pfm-events events:: +Select a PMU event using libpfm4 syntax (see http://perfmon2.sf.net) +including support for event filters. For example '--pfm-events +inst_retired:any_p:u:c=1:i'. More than one event can be passed to the +option using the comma separator. Hardware events and generic hardware +events cannot be mixed together. The latter must be used with the -e +option. The -e option and this one can be mixed and matched. Events +can be grouped using the {} notation. +endif::HAVE_LIBPFM[] + SEE ALSO -------- linkperf:perf-stat[1], linkperf:perf-list[1], linkperf:perf-intel-pt[1] |