Re: speed of deschallmac on PMac 7300/200

Darrell Kindred (dkindred@cmu.edu)
Sun, 25 May 1997 16:53:43 -0400


Arvin Meyer writes:
> [...] The highest statistics seem to have come from 500 MHz DEC Alphas,
> but I haven't seen any statistics from similar Sun and Apple systems (Does
> Apple even make a 500 MHz PowerPC?) If nothing else gets accomplished,
> this knowledge is worth its weight in gold to MIS depts, deciding on major
> equipment purchases.

Keep in mind that DESCHALL clients, both bitslice and
conventional, are a very specialized workload. In
particular, they rarely have to load data from main memory
since the working set typically fits within the L2 cache, if
not the on-chip cache. So DESCHALL tests your CPU (in a
limited way), but not much else. Also, 64-bit processors
have a big advantage in doing bitslice DESCHALL code over
"equivalent" 32-bit processors.

Anyone deciding on equipment purchases would be wise to
consider benchmarks more representative of their expected
typical workloads, unless of course you plan to run only
DESCHALL on your new machines. :)

- Darrell