Re: [RFC/PATCH] perf stat: Show sample events stat for a data file

[Peter Zijlstra <peterz@infradead.org>]

On Wed, Apr 29, 2015 at 04:27:45PM +0900, Namhyung Kim wrote:
> Add --input option to 'perf stat' so that it can show event stats of the
> file.  I would like to use a short '-i' option to be compatible with
> other commands but it was already taken by '--no-inherit' option, so it
> only supports the long option.
> 
> The example output looks like below:
> 
>   $ perf record -a sleep 1
>   [ perf record: Woken up 1 times to write data ]
>   [ perf record: Captured and wrote 0.635 MB perf.data (1946 samples) ]
> 
>   $ perf stat --input perf.data
> 
>     Total event stats for 'perf.data' file:
> 
>               TOTAL events:       6837
>                MMAP events:        116
>                COMM events:        375
>                EXIT events:          2
>            THROTTLE events:         12
>          UNTHROTTLE events:         11
>                FORK events:        374
>              SAMPLE events:       1946
>               MMAP2 events:       3999
>      FINISHED_ROUND events:          2
> 
>    Sample event stats:
> 
>          361,255,234      cycles
>                1,946      samples                   #   sampling ratio  12.162% (486/4000)
> 
>          0.998581085 second time sampled

It would be nice if this thing could support 'perf record -s' which
enables perf_event_attr::inherit_stat, which in turn results in
PERF_RECORD_READ entries after every PERF_RECORD_EXIT which give the
total number of events for each recorded task.