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SubjectRe: What is the performance when using frame pointers in the kernel?
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Jiri Kosina <jkosina@suse.cz> writes:

> 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.

It'll depend on the CPU. On many common cores frame pointer cause
a a few cycles stall on each function entry, but not on all.

-Andi

--
ak@linux.intel.com -- Speaking for myself only.


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