[RC5] RC5-72 G5 core
kakace at wanadoo.fr
Sun Oct 31 08:23:50 EST 2004
Le 31 oct. 04, à 13:18, Jonas Maebe a écrit :
> On 31 Oct 2004, at 08:11, Per Hallström wrote:
>> The G5 processor has been available for a long time now, and the
>> fastest RC5-72 core is still slower (per GHz) than on the G4.
> The G5 is simply slower per MHz/GHz than the G4. For some
> applications, this is offset by the larger memory bandwidth, but rc5
> doesn't care about that. Of course, the G5 also scales much better
> MHz-wise than the G4.
The G5 is actually slower than expected due to a higher lantency
between dependant instructions (2 clock cycles vs 1 on G4).
>> Is there any optimization work in progress? Are there any plans at
>> all for an improved G5 core?
> I don't know. It's of course possible that there are ways to improve
> the keyrate on the G5, but it would surprise me if you could ever get
> a keyrate per MHz comparable to a G4.
A G5 could be 30% faster at RC5, but that'd require a very complex
piece of code to work around the latency issues mentionned above. By
now, nobody was able to write this new core.
More information about the rc5