Optimizations.

[Poul-Henning Kamp]

In message <20030517192323.GA539 at athlon.pn.xcllnt.net>, Marcel Moolenaar writes
:
>On Sat, May 17, 2003 at 07:14:40PM +0200, Poul-Henning Kamp wrote:
>> In message <20030516184626.GB537 at athlon.pn.xcllnt.net>, Marcel Moolenaar writes
>> :
>> >On Fri, May 16, 2003 at 09:59:52AM +0200, Poul-Henning Kamp wrote:
>> >> 
>> >> >That's right:)
>> >> >Look at functions in /sys/kern/kern_tc.c. There are so many little
>> >> >functions. How about put __inline here and there?
>> >> 
>> >> Try it, and you'll find that things get slower because the code
>> >> gets bigger.
>> >
>> >Observed on what architecture?
>> 
>> i386, but it takes a _lot_ to get a stddev on your measurements
>> which allow you to measure this in real-world applications.
>
>Some are called from hardclock so I can imagine that if inlining has
>a positive effect, the effects are generally more indirect. I expect
>that (selective) inlining could make a difference on ia64. There's
>hardly any ILP now. It's also not important now :-)

It all depends on the architecture, and the timecounter hardware.

I _really_ think that there are much more low-hanging fruit for
optimizing performance, than struggling with MD inlining of functions
in the timecounter code.

-- 
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