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Re: CVS commit: src/sys



In article <20111025172130.GA1184@marx.bitnet>,
Jukka Ruohonen  <jruohonen%iki.fi@localhost> wrote:
>On Tue, Oct 25, 2011 at 04:04:35PM +0000, Christos Zoulas wrote:
>> In this case a simple change from:
>>       s += ntb.tv_nsec;
>> to:
>>       s += ntb.tv_nsec / 1000;
>> would have been sufficient since the division is outside the critical
>> sampling section.
>
>Heh, obviously.

I'll put it back then.

>> Could be, but in the long term I prefer us to have only one timing
>> scale in the kernel to avoid conversions, confusion, and gain back
>> some efficiency in the basic timekeeping code which now needs to
>> keep track of both micros and nanos.
>
>Another nice thing would be a KPI for sampling things like this (e.g. more
>robust measures like medium, harmonic mean, etc.). Or even something that
>could enable this kind of profiling on-demand. (I know, DTrace is there.)

I totally agree. Perhaps a SoC project?

christos



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