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SubjectRe: [RFC PATCH 00/10] x86: undwarf unwinder
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Ccing Mel who did proper measurements and can hopefully comment on his
results.

On 06/01/2017, 03:50 PM, Ingo Molnar wrote:
> That's not what I meant! The speedup comes from (hopefully) being able to disable
> CONFIG_FRAME_POINTER, which:
>
> - creates simpler/faster function prologues and epilogues - no managing of RBP
> needed
>
> - gives one more generic purpose register to work from. This matters less on
> 64-bit kernels but it's a small effect.
>
> I've seen numbers of 1-2% of instruction count reduction in common kernel
> workloads, which would be pretty significant on well cached workloads.

thanks,
--
js
suse labs

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