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From: Peter Zijlstra <peterz@infradead.org>
To: Brendan Gregg <brendan.d.gregg@gmail.com>
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Subject: Re: [PATCH/RFC v3] perf core: Allow setting up max frame stack depth
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On Tue, Apr 26, 2016 at 02:58:41PM -0700, Brendan Gregg wrote:
> BTS seemed more promising (deeper stacks), and there's already Xen
> support for it (need to boot the Xen host with vpmu=bts, preferably
> vpmu=bts,arch for some PMCs as well :).

BTS is a branch tracer; it simply traces _all_ branches, including
calls. It has fairly significant overhead.

But yes, by tracing all branches, you should get really shiny call
traces :-)