James Wilkinson wrote:
As processors have got faster, memory hasn't kept up. So a cache miss is proportionately much more expensive, and using cache effectively more important. You can even find people reckoning that x86 these days is competitive with RISC because it's effectively a compression mechanism for RISC code!
If you ask me, it is more like developers of RISC processors are loosing battle on the financial field. You can't really effectivly compete against giant such as Intel in very long term. And RISC processors vere competing against Intel for a very long time now.
RISC processors historicaly have more registers, multiple FPU and integer units, multiple cores (something Intel just started to implement) and so on... But they are lacking in some other areas and basically loosing frequency battle. And really, there is only so much that better design can do against higher frequency... Up until recently, frequencies of RISC processors were at about the same level as Intel processors (with exception of Alpha that was for one period of time way ahead of others on frequency front, but now has fallen way behind Intel). If RISC processor is double the speed than Intel processor at the same frequency, and Intel makes processor that runs at 3 or 4 times higher frequency, than obviously Intel is going to be faster... Not really a rocket science.
-- Aleksandar Milivojevic <amilivojevic@xxxxxx> Pollard Banknote Limited Systems Administrator 1499 Buffalo Place Tel: (204) 474-2323 ext 276 Winnipeg, MB R3T 1L7
