Re: What is the performance when using frame pointers in the kernel?

[Ingo Molnar]

* Justin Piszcz <jpiszcz@xxxxxxxxxxxxxxx> wrote:

> On Fri, 4 Dec 2009, Jiri Kosina wrote:
> 
> >On Thu, 3 Dec 2009, Peter Zijlstra wrote:
> >
> >>>What is the performance hit when the kernel is compiled with frame
> >>>pointers?
> >>
> >>build both kernels and run your favourite workload to find out.
> >
> >But generally speaking, frame pointers impose quite some performance
> >penalty indeed. lmbench syscall microbenchmark can give you some hint. I
> >expect you'll see approx. 10% performance increase for various syscalls if
> >you disable them, as that's what we have measured lately.
> >
> >-- 
> >Jiri Kosina
> >SUSE Labs, Novell Inc.
> >
> 
> Thanks for the response.. Good to know.

I dont buy the 10% without seeing precise measurement results. 1-2% 
maybe, in some cases.

	Ingo
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