From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Thu, 17 Jul 2008 08:56:53 -0400
From: William Josephson <jkw@eecs.harvard.edu>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Message-ID: <20080717125653.GA13591@mero.morphisms.net>
References: <fcdbb29608c689b6f83ca3a2b5539692@quanstro.net>
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Subject: Re: [9fans] 8 cores
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On Thu, Jul 17, 2008 at 08:41:21AM -0400, erik quanstrom wrote:
> as you've pointed out, performance-wise it's not copying vs. nothing
> it's copying vs page faults and trips through the vm code.
> i would think playing vm games (as linus likes to say) would make
> scheduling on mp harder

Munmap is what is really expensive.  The aio stuff exists
under Unix for Oracle and DB2, which is why it only works
for ordinary files in direct I/O mode under Linux.

 -WJ