DragonFly kernel List (threaded) for 2003-11
Re: AMD64 impressions (Re: AMD64 box)
Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx> wrote:
> (1) The AMD box is very fast. Very, very fast. It blows away everything
> else hands down. It is so fast that it spends nearly 1/3 of its
> time waiting on I/O despite the fact that the I/O requirements
> for a buildworld are fairly minimal. It is so fast it makes my P4
> look like a snail, and even puts my DELL2550 (which is no slouch)
> to shame.
> (a) AMD Athlon(tm) 64 Processor 3200+ (2002.57-MHz 686-class CPU)
If you think an Athlon64 is fast, you should get a Tyan Tiger K8S or
Asus SK8N and an Athlon FX51. The dual-channel memory controller of
the Opteron/FX51 vs. Athlon64 gives a very noticable speedup.
> The best comparison is the AMD box verse the P4 box. Both are UP
> boxes. The AMD box is 2.1x faster then the P4 box. If clock speeds
> scaled, that would make the AMD box equivalent to 2.6GHz P4. Since
> clock speeds don't scale, the AMD box is more like a 3.3GHz P4.
> (2) The AMD's syscall overhead is very low compared to the P4.
> I ran the 'sc1' test in /usr/src/test/sysperf. The AMD box
> comes back at 242nS/loop while the P4 takes 1300nS/loop and
> the DELL box (LEAF/SMP) takes 617nS/loop.
We worked on the overall performance of the chip in real-world situations.
Not just paying attention only to those things that raised the MHz and
game FPS benchmarks.
-- David (obrien@xxxxxxxx)