> On Sep 17, 2019, at 11:21 AM, Damjan Marion via Lists.Fd.Io 
> <[email protected]> wrote:
> 
> 
> 
>> On 17 Sep 2019, at 17:12, Christian Hopps <[email protected]> wrote:
>> 
>> 
>> 
>>> On Sep 17, 2019, at 3:56 AM, Benoit Ganne (bganne) via Lists.Fd.Io 
>>> <[email protected]> wrote:
>>> 
>>>>> AFAIK the default for x86_64 is to omit frame pointer
>>>>> for optimized builds so you probably do not have it in most cases in VPP
>>>>> builds (but I did not check).
>>>>> So when perf tries to interpret random data as frame pointer, this is
>>>>> what you get :)
>>>>> The most reliable (but slowest) should be dwarf. lbr should be the way
>>>>> to go on Intel Haswell and later.
>>>> FWIW, this is being run on the Macchiatobin platform (i.e., aarch64
>>>> cortex-A72). :)
>>> 
>>> My bad. Not sure what is going-on but it looks like gcc also omit fp by 
>>> default on aarch64: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84521
>>> Did you had a chance to try dwarf instead of fp?
>> 
>> It doesn't appear to be an option in my perf binary, unfortunately.
> 
> Wasn't much simpler to run "perf top" on the specific core and see where 
> cycles are spent?

This thread sort of forked I think. I was able to run "perf top" as well as 
"perf record" and get some results (indeed including specify a specific core). 
Additionally, I had some doubts about the results at the start of the thread 
b/c of the unexpected symbols that were present in the graph. Benoit has been 
making some suggestions on that (I think! :) front.

IOW I think I'm all good on the perf as far as it goes.

I still think it might be useful to have gprof work, especially if it just 
needs a little tweak somewhere to get working. :)

Thanks,
Chris.

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