speed of disk I/O on PPC

[Garance A Drosihn]

At 9:24 AM +0200 6/27/05, Phil Regnauld wrote:
>Garance A Drosihn (drosih) writes:
>>  me, so I haven't looked into other alternatives.  I am running on
>>  a Mac-mini though, which has a rather slow hard drive (4200 rpm).
>>  So in my case, it's probably faster to stick with the NFS-mounted
>>  directory...    :-)
>
>	Indeed on my G4-450 the disk is running in PIO mode, so NFS
>	is definitely faster...

I just did some buildworld timings on my Mac-mini, which has that
really slow hard drive.  I tried a buildworld with an NFS-mounted
/usr/obj directory, and another with an NFS-mounted /usr/src
directory.  The NFS directories are coming from a i386 machine with
much faster disks.  Oddly enough, the buildworld was faster with
both src and obj as local directories on the slow hard disk.

This was a very simplistic benchmark, and there were some other
things going on at the same time.  Still, I was surprised that
NFS-mounting some directories did not seem to speed anything up.

Both local:  real=5597.58    user=5157.62   sys= 75.53
NFS obj:     real=6543.29    user=5203.52   sys=300.07
NFS src:     real=6703.42    user=5564.93   sys= 90.69

-- 
Garance Alistair Drosehn            =   gad at gilead.netel.rpi.edu
Senior Systems Programmer           or  gad at freebsd.org
Rensselaer Polytechnic Institute    or  drosih at rpi.edu