* Lee Revell <[EMAIL PROTECTED]> wrote:
> I noticed profiling the kernel with PREEMPT_DESKTOP that mcount and
> __mcount add quite a bit of overhead. Something like .5% CPU each.
> Sorry, I didn't save the oprofile output.
>
> So, disable CONFIG_MCOUNT if you want minimal overhead from the RT
> patches. IIRC it was previously stated that the latency tracing
> overhead could be mostly avoided by disabling it at runtime.
yes - most of the overhead can be disabled, but not all. 1% CPU time
might sound alot but when compared against 10% (or more) tracing
overehad it's small. The least overhead comes from disabling tracing in
the .config.
Ingo
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