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# perf record -F 200000 sleep 1
warning: Maximum frequency rate (15,000 Hz) exceeded, throttling from 200,000 Hz to 15,000 Hz.
The limit can be raised via /proc/sys/kernel/perf_event_max_sample_rate.
The kernel will lower it when perf's interrupts take too long.
Use --strict-freq to disable this throttling, refusing to record.
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.019 MB perf.data (15 samples) ]
# perf evlist -v
cycles:ppp: size: 112, { sample_period, sample_freq }: 15000, sample_type: IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1
For those wanting that it fails if the desired frequency can't be used:
# perf record --strict-freq -F 200000 sleep 1
error: Maximum frequency rate (15,000 Hz) exceeded.
Please use -F freq option with a lower value or consider
tweaking /proc/sys/kernel/perf_event_max_sample_rate.
#
Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-oyebruc44nlja499nqkr1nzn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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| .. | ||
| android.txt | ||
| asciidoc.conf | ||
| Build.txt | ||
| callchain-overhead-calculation.txt | ||
| examples.txt | ||
| intel-bts.txt | ||
| intel-pt.txt | ||
| itrace.txt | ||
| jit-interface.txt | ||
| jitdump-specification.txt | ||
| Makefile | ||
| manpage-1.72.xsl | ||
| manpage-base.xsl | ||
| manpage-bold-literal.xsl | ||
| manpage-normal.xsl | ||
| manpage-suppress-sp.xsl | ||
| perf-annotate.txt | ||
| perf-archive.txt | ||
| perf-bench.txt | ||
| perf-buildid-cache.txt | ||
| perf-buildid-list.txt | ||
| perf-c2c.txt | ||
| perf-config.txt | ||
| perf-data.txt | ||
| perf-diff.txt | ||
| perf-evlist.txt | ||
| perf-ftrace.txt | ||
| perf-help.txt | ||
| perf-inject.txt | ||
| perf-kallsyms.txt | ||
| perf-kmem.txt | ||
| perf-kvm.txt | ||
| perf-list.txt | ||
| perf-lock.txt | ||
| perf-mem.txt | ||
| perf-probe.txt | ||
| perf-record.txt | ||
| perf-report.txt | ||
| perf-sched.txt | ||
| perf-script-perl.txt | ||
| perf-script-python.txt | ||
| perf-script.txt | ||
| perf-stat.txt | ||
| perf-test.txt | ||
| perf-timechart.txt | ||
| perf-top.txt | ||
| perf-trace.txt | ||
| perf.data-file-format.txt | ||
| perf.txt | ||
| perfconfig.example | ||
| tips.txt | ||