From mboxrd@z Thu Jan  1 00:00:00 1970
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
In-reply-to: Your message of "Wed, 28 Nov 2012 08:30:49 EST."
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Date: Wed, 28 Nov 2012 10:58:27 -0800
From: Bakul Shah <bakul@bitblocks.com>
Message-Id: <20121128185827.863CFB827@mail.bitblocks.com>
Subject: Re: [9fans] sleep(2) historical question
Topicbox-Message-UUID: ebb297a8-ead7-11e9-9d60-3106f5b1d025

On Wed, 28 Nov 2012 08:30:49 EST erik quanstrom <quanstro@quanstro.net>  wrote:
> On Wed Nov 28 08:11:43 EST 2012, charles.forsyth@gmail.com wrote:
> > No, really, I'm quite serious. A grep of /sys/src/cmd/ suggests that
> > most sleeps are relatively large, and arbitrary.

Chicken and egg.

> > None of the applications look likely to need microsecond let alone
> > nanosecond resolution, and that seems reasonable to me.
> > One exception is sleep(0), but that's yield()
>
> you haven't explained how one can emulate a sub-ms
> sleep with the edf scheduler.  i've got a legit problem.

Why not add nsleep() with sleeptime in nanosecond units?  And
of course, any necessary kernel changes for better accuracy.

The whole idea of a kernel HZ clock seems a bit outdated now.
If the system has nothing do for the next N seconds, it should
may be go into low-power mode & just wait for an interrupt.