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

From: Namhyung Kim
Date: Sat Jan 09 2016 - 04:51:55 EST

On Fri, Jan 08, 2016 at 08:57:05AM +0100, Ingo Molnar wrote:
> * 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.

Not sure. Some people wanted to see more tips more frequently.

I think the 'tip of the day' might be good for regular users, but many
people just use perf when they need it and forget about it soon. For
those people it'd be better to suggest useful tips more often.