From: erik quanstrom <quanstro@quanstro.net>
To: lucio@proxima.alt.za, 9fans@9fans.net
Subject: Re: [9fans] syscall 53
Date: Mon, 19 May 2014 13:25:42 -0400 [thread overview]
Message-ID: <36c5eca0f06e9acbe2fac19067f457d8@ladd.quanstro.net> (raw)
In-Reply-To: <92606a17ce255a2e74049e4090d948b3@proxima.alt.za>
> > i took a quick look at the runtime·nanotime, and it looks like it's being
> > used for gettimeofday, which shouldn't be super performance sensitive.
>
> I'm on thin ice here, but I seem to remember that the crucial issue
> was the resolution (nanosecond) and the expectation that Plan 9 would
> have to match (for portability purposes) the quality available on
> other operating system.
the resolution of the original was already 1ns, the precision and
accuracy were somewhat less, as they would be on any os/hw combination
i am aware of.
> Curiously, I'm pretty certain that it was the issue of an fd that
> remained open (something to do with caching the /dev/time fd, if I
> remember right) that caused some tests to fall apart, probably because
> a test for leaking fds actually needed to cache the time of day for
> time out purposes.
well close the fd then. it's not exceptionally expensive.
> Two birds with one stone? On the one hand you gain accuracy and on
> the other you actually successfully complete the tests.
i would be very surprised if there were any gain in accuracy. the
accuracy is going to be dominated by the most inaccurate term, and
that's likely going to be timesync, and on the order of milliseconds.
- erik
next prev parent reply other threads:[~2014-05-19 17:25 UTC|newest]
Thread overview: 117+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-17 19:11 goo
2014-05-17 21:17 ` Jeff Sickel
2014-05-17 22:21 ` Jeff Sickel
2014-05-17 22:45 ` Skip Tavakkolian
2014-05-18 4:34 ` lucio
2014-05-18 8:29 ` David du Colombier
2014-05-18 15:28 ` Jeff Sickel
2014-05-18 15:32 ` Skip Tavakkolian
2014-05-18 15:34 ` Skip Tavakkolian
2014-05-18 15:38 ` Jeff Sickel
2014-05-18 16:03 ` Skip Tavakkolian
2014-05-18 22:55 ` Skip Tavakkolian
2014-05-19 1:54 ` erik quanstrom
2014-05-19 2:27 ` Jeff Sickel
2014-05-19 4:18 ` lucio
2014-05-19 12:50 ` erik quanstrom
2014-05-19 14:01 ` lucio
2014-05-19 16:24 ` erik quanstrom
2014-05-19 16:54 ` erik quanstrom
2014-05-19 17:16 ` lucio
2014-05-19 17:22 ` erik quanstrom
2014-05-19 17:13 ` lucio
2014-05-19 17:25 ` erik quanstrom [this message]
2014-05-19 19:50 ` Bakul Shah
2014-05-19 19:59 ` erik quanstrom
2014-05-19 20:54 ` ron minnich
2014-05-19 21:30 ` Charles Forsyth
2014-05-19 21:41 ` ron minnich
2014-05-19 23:02 ` Kurt H Maier
2014-05-19 23:06 ` andrey mirtchovski
2014-05-19 23:12 ` Kurt H Maier
2014-05-19 23:17 ` andrey mirtchovski
2014-05-20 0:09 ` Jeff Sickel
2014-05-19 21:34 ` Anthony Sorace
2014-05-20 14:04 ` erik quanstrom
2014-05-20 16:41 ` ron minnich
2014-05-20 17:14 ` erik quanstrom
2014-05-20 18:32 ` Kurt H Maier
2014-05-20 19:49 ` ron minnich
2014-05-20 19:54 ` erik quanstrom
2014-05-20 20:06 ` Kurt H Maier
2014-05-21 10:23 ` hiro
2014-05-20 20:33 ` Jeff Sickel
2014-05-21 1:37 ` Skip Tavakkolian
2014-05-21 15:40 ` lucio
2014-05-21 16:25 ` erik quanstrom
2014-05-21 16:56 ` Skip Tavakkolian
2014-05-21 20:05 ` Steffen Nurpmeso
2014-05-22 0:13 ` Bakul Shah
2014-05-22 3:25 ` [9fans] CMS/MMS (VCS/SCM/DSCM) [was: syscall 53] Jeff Sickel
2014-05-22 5:03 ` lucio
2014-05-22 5:07 ` lucio
2014-05-22 13:29 ` erik quanstrom
2014-05-22 13:50 ` lucio
2014-05-22 5:11 ` Bakul Shah
2014-05-22 5:26 ` lucio
2014-05-22 12:57 ` erik quanstrom
2014-05-22 13:43 ` lucio
2014-05-22 13:57 ` erik quanstrom
2014-05-22 5:28 ` lucio
2014-05-22 5:36 ` lucio
2014-05-22 6:00 ` Bakul Shah
2014-05-22 6:18 ` lucio
2014-05-22 12:45 ` erik quanstrom
2014-05-22 20:05 ` Bakul Shah
2014-05-22 20:11 ` erik quanstrom
2014-05-23 20:07 ` Steve Simon
2014-05-22 9:52 ` Aram Hăvărneanu
2014-05-22 10:29 ` lucio
2014-05-22 10:46 ` Aram Hăvărneanu
2014-05-22 13:03 ` erik quanstrom
2014-05-22 5:23 ` Skip Tavakkolian
2014-05-22 5:47 ` lucio
2014-05-22 12:49 ` erik quanstrom
2014-05-22 7:49 ` Alex Jordan
2014-05-22 12:49 ` Riddler
2014-05-22 3:43 ` [9fans] syscall 53 Kurt H Maier
2014-05-22 5:12 ` lucio
2014-05-22 16:15 ` Kurt H Maier
2014-05-22 5:36 ` Bakul Shah
2014-05-22 10:50 ` Aram Hăvărneanu
2014-05-21 17:01 ` lucio
2014-05-21 17:41 ` erik quanstrom
2014-05-21 19:08 ` lucio
2014-05-21 20:36 ` erik quanstrom
2014-05-22 4:46 ` lucio
2014-05-22 13:18 ` erik quanstrom
2014-05-22 13:39 ` lucio
2014-05-22 14:22 ` Riddler
2014-05-22 4:54 ` lucio
2014-05-22 13:07 ` erik quanstrom
2014-05-21 1:21 ` Skip Tavakkolian
2014-05-21 15:36 ` lucio
2014-05-21 15:57 ` erik quanstrom
2014-05-21 17:03 ` lucio
2014-05-21 16:50 ` Kurt H Maier
2014-05-21 18:02 ` hiro
2014-05-20 17:05 ` Bakul Shah
2014-05-20 17:28 ` erik quanstrom
2014-05-19 17:26 ` Charles Forsyth
2014-05-19 17:29 ` erik quanstrom
2014-05-19 19:15 ` Aram Hăvărneanu
2014-05-19 19:44 ` Charles Forsyth
2014-05-19 20:51 ` erik quanstrom
2014-05-20 3:52 ` cinap_lenrek
2014-05-19 4:15 ` lucio
2014-05-18 0:34 ` erik quanstrom
-- strict thread matches above, loose matches on Subject: below --
2014-05-21 18:26 sl
2014-05-21 18:31 ` erik quanstrom
2014-05-18 7:35 goo
2014-05-17 16:54 goo
2014-05-17 13:53 goo
2014-05-17 14:56 ` erik quanstrom
2014-05-17 10:23 goo
2014-05-17 12:11 ` erik quanstrom
2014-05-17 12:23 ` David du Colombier
2014-05-17 12:12 ` erik quanstrom
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