Messages in this thread | | | Date | Sun, 26 Oct 2008 09:58:01 -0400 (EDT) | From | Steven Rostedt <> | Subject | Re: [PATCH v2][RFC] ftrace: function oprofiler |
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On Sun, 26 Oct 2008, Peter Zijlstra wrote:
> On Sat, 2008-10-25 at 20:55 -0400, Steven Rostedt wrote: > > > This is a function profiler to count the number of times a function is hit. > > I have to ask, _why_? > > It seems like a nice enough gimmick, but is this information actually > useful?
Well, it does let you know for sure which functions are the hottest paths. Perhaps you have a "slow path" function. This will show you how slow that slow path is. That is, how many times it is hit compared to the fast path.
With dynamic ftrace, you can also pick and choose which functions are to be counted.
What is also nice about it (and something that I will use it for), is that it will show you the functions that will be hit the most during a trace. If you do not care about those functions, then you can easily filter them out for your trace.
This patch is also a proof of concept. I'm sure others can think of more useful things to do by adding more stuff to this patch.
-- Steve
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