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Date:   Tue, 22 Mar 2022 17:42:57 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Namhyung Kim <namhyung@kernel.org>
Cc:     Jiri Olsa <jolsa@redhat.com>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Andi Kleen <ak@linux.intel.com>,
        Ian Rogers <irogers@google.com>,
        Stephane Eranian <eranian@google.com>,
        Changbin Du <changbin.du@gmail.com>
Subject: Re: [PATCH 1/2] perf ftrace: Add -n/--use-nsec option for latency
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Em Mon, Mar 21, 2022 at 04:46:08PM -0700, Namhyung Kim escreveu:
> Sometimes we want to see nano-second granularity.
> 
>   $ sudo perf ftrace latency -T dput -a -n sleep 1
>   #   DURATION     |      COUNT | GRAPH                          |
>        0 - 1    us |          0 |                                |
>        1 - 2    ns |          0 |                                |
>        2 - 4    ns |          0 |                                |
>        4 - 8    ns |          0 |                                |
>        8 - 16   ns |          0 |                                |
>       16 - 32   ns |          0 |                                |
>       32 - 64   ns |          0 |                                |
>       64 - 128  ns |    1163434 | ##############                 |
>      128 - 256  ns |     914102 | #############                  |
>      256 - 512  ns |        884 |                                |
>      512 - 1024 ns |        613 |                                |
>        1 - 2    us |         31 |                                |
>        2 - 4    us |         17 |                                |
>        4 - 8    us |          7 |                                |
>        8 - 16   us |        123 |                                |


Thanks, applied.

- Arnaldo