Commit-ID: 239ca3e78609378a1ed5d9db1c7db629a71c2857 Gitweb: https://git.kernel.org/tip/239ca3e78609378a1ed5d9db1c7db629a71c2857 Author: Jin Yao <yao.jin@xxxxxxxxxxxxxxx> AuthorDate: Fri, 30 Nov 2018 21:54:57 +0800 Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> CommitDate: Mon, 17 Dec 2018 14:55:49 -0300 perf report: Documentation average IPC and IPC coverage Add explanations for new columns "IPC" and "IPC coverage" in perf documentation. v5: --- Update the description according to Ingo's comments. Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx> Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx> Reviewed-by: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1543586097-27632-5-git-send-email-yao.jin@xxxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/Documentation/perf-report.txt | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt index 474a4941f65d..ed2bf37ab132 100644 --- a/tools/perf/Documentation/perf-report.txt +++ b/tools/perf/Documentation/perf-report.txt @@ -126,6 +126,14 @@ OPTIONS And default sort keys are changed to comm, dso_from, symbol_from, dso_to and symbol_to, see '--branch-stack'. + When the sort key symbol is specified, columns "IPC" and "IPC Coverage" + are enabled automatically. Column "IPC" reports the average IPC per function + and column "IPC coverage" reports the percentage of instructions with + sampled IPC in this function. IPC means Instruction Per Cycle. If it's low, + it indicates there may be a performance bottleneck when the function is + executed, such as a memory access bottleneck. If a function has high overhead + and low IPC, it's worth further analyzing it to optimize its performance. + If the --mem-mode option is used, the following sort keys are also available (incompatible with --branch-stack): symbol_daddr, dso_daddr, locked, tlb, mem, snoop, dcacheline.
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