Re: [RFC/PATCH v3] perf report: Show random usage tip on the help line

From: Ingo Molnar
Date: Fri Jan 08 2016 - 02:57:14 EST

* Namhyung Kim <namhyung@xxxxxxxxxx> wrote:

> Currently perf report only shows a help message "For a higher level
> overview, try: perf report --sort comm,dso" unconditionally (even if
> the sort keys were used). Add more help tips and show randomly.
> Load tips from ${prefix}/share/doc/perf-tip/tips.txt file.

> +++ b/tools/perf/Documentation/tips.txt
> @@ -0,0 +1,14 @@
> +For a higher level overview, try: perf report --sort comm,dso
> +Group related events with: perf record -e '{cycles,instructions}:S'
> +Compare performance results with: perf diff [<old file> <new file>]
> +Boolean options have negative forms like: perf report --no-children
> +Customize output of perf script with: perf script -F event,ip,sym
> +Generate a script for your data: perf script -g <lang>
> +Save output of perf stat using: perf stat record
> +Create archive of data to see it on other machine: perf archive
> +Search options using a keyword: perf report -h <keyword>
> +Use parent filter to see specific call path: perf report -p <regex>
> +listing interested events using substring match: perf list <keyword>
> +To see list of saved events and attributes: perf evlist -v
> +Use --symfs <dir> if your symbol files are in non-standard location
> +To see callchains in a more compact form: perf report -g folded

Very nice!

Acked-by: Ingo Molnar <mingo@xxxxxxxxxx>

On top of this, what do you think about only doing a single tip per day, the 'tip
of the day'? That would have two effects:

- people who know all this already see this less

- people who don't know all this will perhaps be more attentive, because a tip
for every report is more likely to get ignored.

This could be done via a flag in ~/.perf/ or so.

Another suggestion: shouldn't the tips be tool specific, i.e. shouldn't there be a
tip-report.txt, tip-record.txt, etc. set of files?