Re: [parisc-linux] Re: Problem installing .9 iso image on C240

[Grant Grundler <grundler@puffin.external.hp.com>]

Paul Bame wrote:
> I don't know that a 64-bit kernel buys you much on a C240 -- am I mistaken?

I think not.

I thought about making the same comment since in general wide-mode
just runs 2-5% slower. But some apps could take advantage of the wider
words for substantial perf gains...but since we don't support 64-bit apps
(yet) and only a few isolated places in the kernel would benefit (eg
cksum'ing code), I don't see 64-bit kernel a "must have" for C240.

> = > PDC on the C240 (and similar C-models of that generation) only
> = > support PDC calls in "narrow" (ie 32-bit) mode. Sounds like the decision
> = > to install 32 vs 64-bit depends on the PDC capabilities bit.
> = > Can anyone offhand confirm/deny?
> 
> Yes, palo asks the firmware whether one or both of 32&64-bit OSs will
> run on the box.  Cxxx says 32 bit only.  If both are possible, palo
> chooses 32-bit for now.

Ok - thanks!
And I think that's fine in general. Someone with a specific
need for 64-bit ops can build/install a 64-bit kernel after the fact.
Someday we might have a real 64-bit userspace and it might be interesting
to get pickier about install support for PA2.0 CPU's.

grant

Grant Grundler
parisc-linux {PCI|IOMMU|SMP} hacker
+1.408.447.7253