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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] interesting timing tests
Date: Sun, 20 Jun 2010 08:45:35 -0400	[thread overview]
Message-ID: <1e3839eef0747b0e90b5ae21a71e41ce@kw.quanstro.net> (raw)
In-Reply-To: <6fab54d97a1b61a333f755f0595b6968@hamnavoe.com>

> Spin locks would have been high on my list of suspects.

mine, too.  the 64 bit question is, which spin locks.

>
> > i'm less sure that runproc is really using 62% of the cpu
>
> Not impossible, given this:
>
> Proc*
> runproc(void)
> {
> 		...
> 		/* waste time or halt the CPU */
> 		idlehands();
> 		...
>
> and this:
>
> void
> idlehands(void)
> {
> 	if(conf.nmach == 1)
> 		halt();
> }

yet for one machine conf.nmach == 4 and for the
other conf.nmach == 16; neither is calling halt.

- erik



  reply	other threads:[~2010-06-20 12:45 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-06-18 23:26 erik quanstrom
2010-06-19 13:42 ` Richard Miller
2010-06-20  1:36   ` erik quanstrom
2010-06-20  7:44     ` Richard Miller
2010-06-20 12:45       ` erik quanstrom [this message]
2010-06-20 16:51         ` Richard Miller
2010-06-20 21:55           ` erik quanstrom
2010-06-21  1:41             ` erik quanstrom
2010-06-21  3:46               ` Venkatesh Srinivas
2010-06-21 14:40                 ` erik quanstrom
2010-06-21 16:42                   ` Venkatesh Srinivas
2010-06-21 16:43                   ` erik quanstrom
2010-06-21 21:11 ` Bakul Shah
2010-06-21 21:21   ` erik quanstrom
2010-06-21 21:47     ` Bakul Shah
2010-06-21 22:16       ` erik quanstrom
2010-06-22  3:24 ` Lawrence E. Bakst
2010-06-23  1:09   ` erik quanstrom

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