Jeremy Katz wrote:
On Monday, January 19 2009, Avi Kivity said:
Jeremy Katz wrote:
That said, we currently do install the PAE kernel if you have 4 GB+ of RAM[1]. Switching to it by default is problematic because then we're back to using different kernels for different cases
You have that now, don't you? One case for <4GB and one for >=4GB. Worse, if you install more memory, the kernel doesn't see it.
Downgrading your CPU to one which does not support PAE should be rare.
Yes, but at least the "running a different kernel" case is currently the relatively rare one.
It will become more and more frequent as machines get beefier. If we switch to PAE, it will be the non-PAE case which is rare.
btw, what's wrong with running a different kernel? So long as the configs match, there shouldn't be a difference in reliability.
and it also makes the 'what do you with the live image' case a lot more complex.
I'd just go with PAE here.
Can't do so -- the live image is definitely used on a lot of hardware that isn't PAE capable. Many/most Pentium M's didn't support it, the OLPC doesn't[1]. And those are common hardware targets for the live image
So either put both kernels there, or the non-PAE kernel.
The _real_ fix here is to get PAE runtime much like was finally done with SMP :-)
Patches, as they say, are welcome.
Low-level x86 setup code isn't quite my forte... Hence I go for goading others into doing it ;-)
I meant, "this requires a monumental amount of work".
But you could install both kernels and have the bootloaded choose (sticks wax balls into ears).
Want to write code for syslinux and grub to do the auto-choosing?
Not really. I don't see it as particularly difficult.
With grub, you could use multiboot to add a module to select the correct kernel, maybe.
I think Windows works this way, with the /PAE switch on the kernel command line causing a different kernel to be loaded.
Then we also have to figure out a way to shoe-horn another 50 MB of stuff into the already full live image
Cut away the drivers for Infiniband and similarly useless hardware (for livecds, that is). Put them in a separate subpackage or use steam-powered rm -rf.