From mboxrd@z Thu Jan  1 00:00:00 1970
From: erik quanstrom <quanstro@labs.coraid.com>
Date: Wed, 28 Nov 2012 14:28:53 -0500
To: 9fans@9fans.net
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Subject: Re: [9fans] sleep(2) historical question
Topicbox-Message-UUID: ebf2157c-ead7-11e9-9d60-3106f5b1d025

10ms, the current limit to sleep resolution from sources,
is a massive chunk of time.  even 100=C2=B5s 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