diff options
Diffstat (limited to 'tools/perf/Documentation/perf-top.txt')
| -rw-r--r-- | tools/perf/Documentation/perf-top.txt | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/tools/perf/Documentation/perf-top.txt b/tools/perf/Documentation/perf-top.txt index 114fda12aa49..808b664343c9 100644 --- a/tools/perf/Documentation/perf-top.txt +++ b/tools/perf/Documentation/perf-top.txt @@ -242,6 +242,16 @@ Default is to monitor all CPUS. --hierarchy:: Enable hierarchy output. +--overwrite:: + Enable this to use just the most recent records, which helps in high core count + machines such as Knights Landing/Mill, but right now is disabled by default as + the pausing used in this technique is leading to loss of metadata events such + as PERF_RECORD_MMAP which makes 'perf top' unable to resolve samples, leading + to lots of unknown samples appearing on the UI. Enable this if you are in such + machines and profiling a workload that doesn't creates short lived threads and/or + doesn't uses many executable mmap operations. Work is being planed to solve + this situation, till then, this will remain disabled by default. + --force:: Don't do ownership validation. |