Re: [PATCH v2 3/7] Adding general performance benchmarking subcommand to perf.

[Ingo Molnar <mingo@elte.hu>]

* Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> wrote:

> From: Ingo Molnar <mingo@elte.hu>
> Subject: Re: [PATCH v2 3/7] Adding general performance benchmarking subcommand to perf.
> Date: Mon, 9 Nov 2009 08:55:12 +0100
> 
> > 
> > * Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> wrote:
> > 
> > > From: Ingo Molnar <mingo@elte.hu>
> > > Subject: Re: [PATCH v2 3/7] Adding general performance benchmarking subcommand to perf.
> > > Date: Sun, 8 Nov 2009 12:30:13 +0100
> > > 
> > > > > > 
> > > > > > Shouldnt we output the unit of measurement, i.e. '4.575 usecs'? Also, we 
> > > > > > should perhaps print something like:
> > > > > > 
> > > > > >   % perf bench sched pipe
> > > > > > 
> > > > > >   (executing 1000000 pipe operations between two tasks)
> > > > > > 
> > > > > >      4.575 usecs per op
> > > > > >     218579 ops/sec   
> > > > > > 
> > > > > > ?
> > > > > 
> > > > > I have to admit that single float value output is too simple.
> > > > > So I'll fix the default output.
> > > > > 
> > > > > But, I believe that simple form makes sense for
> > > > > processing by scripts or graph tools like gnuplot.
> > > > > I'll add the option (may be --simple) to switch
> > > > > friendliness of outputs.
> > > > 
> > > > Btw., could you make it Git-ish, i.e.:
> > > > 
> > > >  --format=short
> > > > 
> > > > or:
> > > > 
> > > >  --format=simple
> > > > 
> > > > Eventually more format options might be added.
> > > 
> > > It's good idea.
> > > I have to admit that reserving -s for simple output is not good idea.
> > > I'll do this.
> > 
> > I think --format=simple will be used by scripts mostly, so it doesnt 
> > matter that it's longer to type. We try to save the shorter options for 
> > humans and be conservative with them.
> > 
> > Another angle is coherency between different subcommands - and '-s' is 
> > already used as -s/--sort in other perf subcommands, which does not 
> > match up with the '-s/--simple' usage.
> > 
> > We try to match what the Git project does here - a good deal of 
> > infrastructure code in perf came from Git and i find Git very easy to 
> > use and it's managed well.
> > 
> > It's not a hard rule: not all option name incoherencies are fixable or 
> > avoidable, and there's no big problem if something slips in - i just 
> > wanted to mention so that you can keep an eye on it when developing new 
> > features for perf bench.
> > 
> > 	Ingo
> > 
> 
> I added --format as option of bench subcommand,
> not of each suites.
> Because I thought that flavors of formatting are common thing
> across the suites.

yeah. Maybe it might be librarized into util/ as well in the future, if 
another perf subcommand wants to pick it up.

> 
> Example of use:
> % ./perf bench sched pipe           # with no style specify
> (executing 1000000 pipe operations between two tasks)
> 
>         Total time:5.855 sec
>                 5.855061 usecs/op
>                 170792 ops/sec
> % ./perf bench --format=simple sched pipe # specified simple
>                ^^^^^^^^^^^^^^^	# <- --format is here
> 5.988
> 
> How do you think?
> I'll send patch series later.

Looks good - i picked them up.

Thanks,

	Ingo