Benchmarks: AMD64 vs i386 on Dual 246 Opteron

[ray at redshift.com]

At 11:13 AM 8/2/2005 -0700, David O'Brien wrote:
| On Tue, Aug 02, 2005 at 10:59:41AM -0700, ray at redshift.com wrote:
| > Thanks David - needless to say, I'm going to be re-running all my benchmarks
| ...
| > I'll post my results when I have another machine in here and re-run the exact
| > same benchmarks.  This time I will be certain to confirm the situation on the
| > SMP kernel with regard to the AMD64 branch.
| 
| You need to be careful about what you are testing.
| If you dual-boot 64-bit and 32-bit from the same disk, don't forget one
| of them will be on a faster area of the disk.  So you need a 2nd data
| disk that is newfs'ed between each run to do your benchmarks on.
| 
| At a minium, you should build a set of 32-bit binaries on FreeBSD/i386
| with CPUTYPE=k8.  Run benchmarks under the 32-bit OS.
| Then run the same benchmarks with the 32-bit binaries on the 64-bit OS.
| (ie, you're just changing the kernel).
| Then build 64-bit binaries and benchmark them.
| You should use RELENG_6, not 5.x to make sure you're getting the best K8
| GCC we support along with the optimizations we've added since 5.x was
| released.
|  
| -- 
| -- David  (obrien at FreeBSD.org)

okay, thanks for the info. I'll keep that handy for when I have another machine
to test.

Ray