Re: Why HZ on i386 is 100 ?

Martin Dalecki (dalecki@evision-ventures.com)
Wed, 17 Apr 2002 12:12:12 +0200


Linus Torvalds wrote:
>
> On Wed, 17 Apr 2002, Mark Mielke wrote:
>
>>On Tue, Apr 16, 2002 at 08:57:09PM -0400, Robert Love wrote:
>>
>>>Because that is what Alpha does? It seems to me there is no reason for
>>>a power-of-two timer value, and using 1024 vs 1000 just makes the math
>>>and rounding more difficult.
>>
>>Only from the perspective of time displayed to a user... :-)
>
>
> No, it also makes it much easier to convert to/from the standard UNIX time
> formats (ie "struct timeval" and "struct timespec") without any surprises,
> because a jiffy is exactly representable in both if you have a HZ value
> of 100 or 100, but not if your HZ is 1024.

And infally 100HZ is (by accident) quite right on the perceptive
threshold of a human, which is about 0.15 of a second :).

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