From: Bakul Shah <bakul@bitblocks.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] sleep(2) historical question
Date: Wed, 28 Nov 2012 10:58:27 -0800 [thread overview]
Message-ID: <20121128185827.863CFB827@mail.bitblocks.com> (raw)
In-Reply-To: Your message of "Wed, 28 Nov 2012 08:30:49 EST." <0cf8de222eb5fa81721e8bcf4dd4e875@brasstown.quanstro.net>
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The whole idea of a kernel HZ clock seems a bit outdated now.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.
next prev parent reply other threads:[~2012-11-28 18:58 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-27 23:19 erik quanstrom
2012-11-28 7:37 ` Charles Forsyth
2012-11-28 12:57 ` erik quanstrom
2012-11-28 13:10 ` Charles Forsyth
2012-11-28 13:30 ` erik quanstrom
2012-11-28 14:35 ` Charles Forsyth
2012-11-28 14:46 ` erik quanstrom
2012-11-28 18:58 ` Bakul Shah [this message]
2012-11-28 19:10 ` Charles Forsyth
2012-11-28 19:28 ` erik quanstrom
2012-11-28 18:56 ` cinap_lenrek
2012-11-28 19:38 ` Bakul Shah
2012-11-28 20:58 ` Charles Forsyth
2012-11-28 21:02 ` erik quanstrom
2012-11-28 21:13 ` Charles Forsyth
2012-11-28 21:19 ` erik quanstrom
2012-11-28 21:21 ` erik quanstrom
2012-11-28 21:43 ` Bakul Shah
2012-11-29 0:12 ` Charles Forsyth
2012-11-29 8:12 ` arnold
2012-11-29 9:19 ` Charles Forsyth
2012-11-29 15:17 ` erik quanstrom
2012-11-28 19:27 ` David Arnold
2012-11-28 21:12 ` Charles Forsyth
2012-11-28 19:29 ` erik quanstrom
2012-11-28 19:54 ` Bakul Shah
2012-11-28 19:57 ` erik quanstrom
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