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Re: Yaboot Config Question

>My very subjective impression is that compiling (kernels, or anything
>else, for that matter) _is_ slower on PPC than on i386. No hard figures
>here; but that has been my impression all the time during the 4 years
>I'm following PPC Linux.
>Reasons might be many and various: memory bandwidth being _much_ lower
>on all but the latest Apple machines, compared to equivalent i386 boxes,
>being one of them. RISC vs. CISC code generation might be another, also
>that is pure speculation on my part. Different levels of compiler
>omptimisation might be another.

Note that all recent Apple machines (the "core99" series) have a very much
higher memory bandwidth (100Mhz on a 64 bits wide bus and better memory
controller) than any previous model.
Also, the page copy optimisations Paulus added to 2.4 seem to give full
on G4 CPUs (better cache management than G3s ?) to reach about 200Mb/sec on a
G4/350 with the hdparm buffer cache test.

I've been told (but didn't actually verify this with benches) that latest
Apple desktop G4s have bumped the bus speed once again to reach 133Mhz.


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