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* why is CONFIG_FRAME_POINTER=y so expensive?
@ 2016-08-22  6:17 Mike Galbraith
  0 siblings, 0 replies; only message in thread
From: Mike Galbraith @ 2016-08-22  6:17 UTC (permalink / raw)
  To: LKML; +Cc: Ingo Molnar

Greetings,

tbench 8 throughput on my i4790 box:
                              1        2        3      avg
master                  3769.95  3759.28  3762.83  3764.02  1.000
master-framepointer     3476.73  3453.52  3460.62  3463.62   .920

Does anyone know why the performance impact is this large?

The only thing I found googling was a reference to 3 arg lea using rbp
or r13 being slow, which wasn't particularly helpful.  Nor was staring
at asm deltas with non-expert eyeballs.

	-Mike

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2016-08-22  6:17 why is CONFIG_FRAME_POINTER=y so expensive? Mike Galbraith

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