From: Lee Revell <rlrevell@joe-job.com>
To: Albert Cahalan <acahalan@gmail.com>
Cc: linux-kernel@vger.kernel.org, kernel@kolivas.org,
john stultz <johnstul@us.ibm.com>
Subject: Re: [ckpatch][15/29] hz-no_default_250.patch
Date: Sun, 18 Jun 2006 21:30:31 -0400 [thread overview]
Message-ID: <1150680632.4428.129.camel@mindpipe> (raw)
In-Reply-To: <787b0d920606181752j4b7c7309t9c0ab9bf8da1537a@mail.gmail.com>
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
next prev parent reply other threads:[~2006-06-19 1:30 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-06-19 0:52 [ckpatch][15/29] hz-no_default_250.patch Albert Cahalan
2006-06-19 1:25 ` Con Kolivas
2006-06-19 11:52 ` Jan Engelhardt
2006-06-21 4:53 ` Con Kolivas
2006-06-19 1:30 ` Lee Revell [this message]
2006-06-19 1:52 ` Con Kolivas
-- strict thread matches above, loose matches on Subject: below --
2006-06-18 7:32 Con Kolivas
2006-06-18 7:42 ` Willy Tarreau
2006-06-18 10:08 ` Con Kolivas
2006-06-18 15:03 ` Jan Engelhardt
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