Re: [lm@bitmover.com: Linux performance vs IRIX performance]

[ralf@uni-koblenz.de]

On Sat, Jul 18, 1998 at 06:02:25PM +0200, Andi Kleen wrote:

> ralf@uni-koblenz.de writes:
> 
> > A factor of 4.4 difference.  It's not fair to actually expect that good of
> > a result - the SGI OS is an SMP OS that scales up to approximately 128 
> > processors, has all sorts of useful and not so useful features that Linux
> > doesn't have, etc, etc.  None the less, it is likely that Linux on the same
> > hardware would be about 3 times faster than IRIX.  
> 
> Larry did not say what kind of FS he used on the Irix box (XFS or EFS), but
> for me it looks like a typical sync metadata/async metadata comparison.

Whatever - the impact of the dcache on the performance is sometimes really
amazing.  As long as Linux doesn't hit the disk on an Indy it is _much_
faster than IRIX.  For the normal case XFS and ext2 aren't too far from
each other.  Finally when Linux hits the disk it looses badly, the current
wd33c93 driver performs pretty badly.

  Ralf