Re: [RFC/PATCHSET 00/17] perf tools: Add support for hierachy view (v2)

[Namhyung Kim]

On Tue, Jan 19, 2016 at 05:59:41PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Sun, Jan 17, 2016 at 01:03:00AM +0900, Namhyung Kim escreveu:
> > Hello,
> > 
> > This is v2 attempt of my earlier patchset [1].  This patchset
> > implements a new feature that collects hist entries in a hierachical
> > manner.  That means lower-level entries belong to an upper-level
> > entry.  The entry hierachy is built on the sort keys given, so users
> > can set it whatever they want.  It only shows top-level entries first,
> > and user can expand/collapse it dynamically.
> > 
> > This time I implemented it for every output browser including TUI.
> > A screenshot on TUI looks like below:
> > 
> > For normal output:
> > 
> >   $ perf report --tui
> >   Samples: 3K of event 'cycles:pp', Event count (approx.): 1695979674
> >     Overhead  Command        Shared Object         Symbol
> >   ------------------------------------------------------------------------
> >   -    7.57%  swapper        [kernel.vmlinux]      [k] intel_idle
> >        intel_idle
> >        cpuidle_enter_state
> >        cpuidle_enter
> >        call_cpuidle
> >      + cpu_startup_entry
> >   +    1.16   firefox        firefox               [.] 0x00000000000019433
> >   +    0.97%  firefox        libpthread-2.22.so    [.] pthread_mutex_lock
> >   ...
> > 
> > 
> > With hierarchy view,
> 
> Ok, tested, this is really nice, I think it should be the default, from
> where to drill down, we could have a '--no-hierarchy', Ingo?

Yeah, we already have --no-hierarchy (as a side effect of having
--hierarchy) but I don't want to change the default now since existing
users will complain.  Now we have 'tips' in the perf report browser,
maybe it's enough to add a line to suggest to use it (and it's already
done by this patchset).  I remember the time we changed default for
'--children' and many people complained about it.

We maybe change the default later but I think it's better to have some
time to people can play with it and find it useful. :)  And, as always,
we can have a config option to control the default.

Btw, do you think it's worth adding a short option (-H) for
--hierarchy (instead of making it default)?

Thanks,
Namhyung


> 
> I'll took a quick look patch by patch, seems ok, will try to look deeper
> to get this merged soon,
> 
> keep up the great work!