On Tuesday 20 August 2002 08:57, Paul Leyland wrote: > Anyone else here old enough to remember Meaningless Indicators of Processor > Speeds?
Oh yes. My first boss used to rate CPUs in "Atlas power".... > > All gigaflops are not created equal, unfortunately. Wordlength alone can > make a big difference. Really we need only consider IEEE single (24+8) & double (53+11) precision types... the x87 80-bit format is not much different to double precision the way we use it, and I'm not aware of any common hardware implementations of other floating-point formats. > > > Or use bogomips... :) > > It's no worse than many suggestions, and better than some we've seen. Surely bogomips is measured only in the integer arithmetic unit? > > Personally I vote for the status quo. It's a well understood arbitrary > unit and there are enough P90's around to be able to re-calibrate new > algorithms as they come along. If need be, I can un-overclock my P120 to > convert it back into a P90 for benchmarking purposes. I doubt very much > that there aren't other P90 owners who could also provide a similar > service. There's a great deal to be said for that proposal. But don't forget that the "official P90 benchmark" refers to a specific system, no longer in existence, operated by George Woltman; it seems to have been a rather good P90 system. Apart from the CPU, factors such as the L2 cache size, memory timings, chipset type, BIOS parameters etc. etc. can make a significant difference to the speed of a system. Regards Brian Beesley _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
