Commit-ID: b63940970492f5f187d546e191bc2c6831491fe3 Gitweb: http://git.kernel.org/tip/b63940970492f5f187d546e191bc2c6831491fe3 Author: Andi Kleen <ak@xxxxxxxxxxxxxxx> AuthorDate: Fri, 28 Feb 2014 06:02:14 -0800 Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> CommitDate: Fri, 14 Mar 2014 11:20:44 -0300 perf mem: Clarify load-latency in documentation Clarify in the documentation that 'perf mem report' reports use-latency, not load/store-latency on Intel systems. This often causes confusion with users. Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1393596135-4227-2-git-send-email-andi@xxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/Documentation/perf-mem.txt | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/perf/Documentation/perf-mem.txt b/tools/perf/Documentation/perf-mem.txt index 888d511..1d78a40 100644 --- a/tools/perf/Documentation/perf-mem.txt +++ b/tools/perf/Documentation/perf-mem.txt @@ -18,6 +18,10 @@ from it, into perf.data. Perf record options are accepted and are passed through "perf mem -t <TYPE> report" displays the result. It invokes perf report with the right set of options to display a memory access profile. +Note that on Intel systems the memory latency reported is the use-latency, +not the pure load (or store latency). Use latency includes any pipeline +queueing delays in addition to the memory subsystem latency. + OPTIONS ------- <command>...:: -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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