Yokemate of Keyboards
Posts: 11554 from 2003/5/22
> If we had hardware that used those processors then I would agree with you. But the
> X5000 variant soon to be launched (in two weeks?) is P5020 based. A dual core.
Indeed, I was using the announced P5040-based X5000/40 to illustrate the top e5500 core count and performance.
>> I think it's a given that the non-SIMD per-clock performance of the e6500 is less
>> than 22% higher than that of the e5500 so won't make up for the clock rate decrease.
> the performance increase of the e6500 seems to provide exactly what is necessary to
> cover the decreased frequency. [...] So, in a non-SIMD application we have parity [...].
> [...] Without SIMD, the e6500 based cpus [...] offer parity with the P5020/P5040
As said, this required increase would be 22% to be on par with P5040 and 11% to be on par with P5020. Increase of DMIPS per clock and thread is between 3% and 10% (depending on source) in single-thread use according to Freescale documents
>> SMP would be fine with 4 e5500 cores in the P5040 and the T1042, and I have doubts
>> that more cores can be frequently saturated with common desktop computing tasks.
> e6500 cores are dual threaded and [...] the minimum number of cores is 4. [...] with
> SMP we have four times the processing power than with a P5020. That is still twice
> what the P5040 could manage. [...] it really would take SMP support to really make
> the 6500 based cpus perform optimally.
As said, I doubt that more than 4 threads can be frequently saturated with common desktop computing tasks.
> then there is the issue of Altivec....
Yes, that's the glimmer of hope if used extensively.
> this is about the X5000 and the P5020 and P5040 processors used on those boards.
> My primary objection to those two cpus is price, A T1042, T2081, or even a T2080
> would all be cheaper solutions. The T1042 is obviously slower than the P5040, but
> at about $200 less, it could provide a significant price reduction. [...]
> the e6500 based cpus [...] have a price advantage over the cpus used in the X5000.
We are talking about whether or not the e6500 can be the real performance upgrade the e5500 apparently isn't (according to first benchmarks, that is), so T1 is out of this discussion obviously.
1.8 GHz T2080 is less than 100 USD cheaper than 2.2 GHz P5040. The question is if 100 USD really matter with a 2000+ USD board. That's less than 5% price difference.
> I was hoping that the performance of the X5000 would be a significant improvement
> over our current hardware
Over G4 yes, over G5 no (in terms of CPU performance, that is).
> it may top our G4 based systems
1.5 GHz G4 in terms of CPU performance, yes. This will look differently with faster G4 systems.
> the G5 is still probably the more powerful solution.
I guess so.
> that would be the comparison I'd like to see, X5000 vs PCIe G5.
I'd be content with a comparison with pre-PCIe G5. After all, it runs MorphOS for better comparability, and single-core CPU performance wasn't increased significantly (2.7 GHz PPC970FX is probably faster than 2.5 GHz PPC970MP in single-core performance).