Re: [ckpatch][15/29] hz-no_default_250.patch

[Lee Revell]

On Sun, 2006-06-18 at 20:52 -0400, Albert Cahalan wrote:
> > Make 250 HZ a value that is not selected by default and give some
> > better recommendations in help.
> 
> No, 250 is a good default.
> 
> We can't reliably do 1000. There are many systems, including both
> laptops and servers, which have a BIOS that uses SMM/SMI to grab
> the CPU for longer than a millisecond. We'd lose clock ticks if
> we had HZ at 1000.
> 

Doesn't this become a non-issue with John Stultz's gettimeofday rework?

> NTSC video is 59.94 fields per second. Though a sample rate of
> double that would satisfy the Nyquest theory, in practice you
> need to go to 4x to 5x the rate you want. This comes out to be
> around 240 to 300 as a minimum.

Realtime audio wants higher framerates than video.  Of course many of
these systems with the SMM bug are fatally broken for these
applications.

Lee

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