Features/ArchitectureSupport - changing what we build for

[Benny Amorsen]

Chris Adams <cmadams at hiwaay.net> writes:

> IIRC, I asked about this a few years ago and got told that there was a
> performance hit (not big but measurable) for running the 64 bit kernel
> and 32 bit userland.  Maybe that was wrong or is now outdated.

It should be the other way around -- 64 bit kernel should be faster.
The only downside is that the kernel may take a little more memory,
but that isn't really a problem for non-embedded systems.

> What are the chances GRUB/syslinux could be taught to look at a few
> special CPU flags (can you fetch the important flags from real mode?)
> and only present "compatible" (as determined by config arguments, not
> GRUB/syslinux poking into kernels) boot options?  That would help the
> LiveCD case as well.  You could have both 32-PAE and 64 kernels on the
> CD and choose at boot time, although that would take up a large amount
> of space (so maybe not feasible for LiveCD).

That would be rather neat. Tricky, but neat.


/Benny