Subject: Re: mfs changes [thorpej@netbsd.org: CVS commit: syssrc]
To: Simon Burge <simonb@netbsd.org>
From: Jason R Thorpe <thorpej@zembu.com>
List: tech-kern
Date: 05/22/2000 18:38:16
On Tue, May 23, 2000 at 11:22:52AM +1000, Simon Burge wrote:

 > Interesting how if anything there's a slight decrease in performance.
 > The full CPU utilitisation is obviously because there's no context
 > switch overhead at all...  I hand edited the "100." bits - bonnie didn't
 > cater for "100.0" in the %CPU columns :-)

That's not entirely surprising -- the "new" mfs (which is backed out) incurs
more TLB flush overhead, especially on systems that implement address space
identifiers (like the Alpha 21164 and higher, and MIPS); on such systems,
there is no TLB flushing on context switch because of the address space ID.

-- 
        -- Jason R. Thorpe <thorpej@zembu.com>