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

[Namhyung Kim <namhyung@kernel.org>]

On Fri, Jan 08, 2016 at 09:54:41AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Fri, Jan 08, 2016 at 08:57:05AM +0100, Ingo Molnar escreveu:
> > 
> > * Namhyung Kim <namhyung@kernel.org> 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@kernel.org>
> > 
> > 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?
> 
> Yeah, we could have per tool tip files, but then sometimes to use a
> feature in 'report' we have to first use some magic combination on the
> 'record' command line.

Right.  In addition, tips can depend on configurations, runtime
environment and so on.  But let's leave it as later work. :)


> 
> Anyway, I think I'll apply Namhyung's latest, the one in this message,
> and get the basic stuff in, we then go on improving on it.

Agreed!

Thanks,
Namhyung