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From: erik quanstrom <quanstro@labs.coraid.com>
To: 9fans@9fans.net
Subject: Re: [9fans] sleep(2) historical question
Date: Wed, 28 Nov 2012 14:28:53 -0500	[thread overview]
Message-ID: <65a29adb6589803f9c01d0e1af5441d9@coraid.com> (raw)
In-Reply-To: <CAOw7k5iaYTkyXL4WrVyeVEU4daEWKYxxN_AQhd0nRFsexctJJg@mail.gmail.com>

10ms, the current limit to sleep resolution from sources,
is a massive chunk of time.  even 100µs is a rather large chunk
of time these days.  10 millisecond is
- 12.5 MB on a 10gbe network (1.25mb on gbe) or 1000 rtt (100rtt)
- 30 million instructions (per core), assuming only scalar.

On Wed Nov 28 14:11:58 EST 2012, charles.forsyth@gmail.com wrote:
> No, I don't think it is, in this case. I really don't see many
> applications deeply yearning for tiny sleeps and naplets.

even usb/kb uses sleep(5), which isn't going to work as intended.
that's getting pretty close to the limit.

ping is an example of a little program that really could use better
timing.  ping -i sets the interval between frames using sleep.
a minimum interval of 1000 rtt really limits the utility.

i think you're arguing for making anything about that granularity
*impossible*.

- erik



  reply	other threads:[~2012-11-28 19:28 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
2012-11-28 19:10           ` Charles Forsyth
2012-11-28 19:28             ` erik quanstrom [this message]
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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