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

From: Taeung Song <taeung.dev@gmail.com>
To: Namhyung Kim <namhyung@kernel.org>,
	Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Jiri Olsa <jolsa@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
	David Ahern <dsahern@gmail.com>,
	Stephane Eranian <eranian@google.com>,
	Andi Kleen <andi@firstfloor.org>, Wang Nan <wangnan0@huawei.com>,
	Don Zickus <dzickus@redhat.com>,
	Pekka Enberg <penberg@kernel.org>,
	Moinuddin Quadri <moin18@gmail.com>
Subject: Re: [RFC/PATCHSET 00/17] perf tools: Add support for hierachy view (v2)
Date: Wed, 20 Jan 2016 16:49:29 +0900	[thread overview]
Message-ID: <569F3C09.8070903@gmail.com> (raw)
In-Reply-To: <20160120003451.GB18796@sejong>

On 01/20/2016 09:34 AM, Namhyung Kim wrote:
> 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.

If adding this config option,
can this be included in 'hist' section ?
If it isn't, 'report' and 'top' section ?
i.e.

[report]
     hierarchy = true
[top]
     hierarchy = false

Thanks,
Taeung

>
> 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!