For the past month or so, whenever I run SMXI on my Debian-Testing distro, it tells me that I need to upgrade the Linux kernel. Fair enough, except the choice is to upgrade to kernel version 2.6.32-5-686. However, I currently have version 3.2.0-3-686-pae installed.

I'm using a fairly ancient computer, with an Intel Core2 Duo CPU E8400 @ 3.00GHz CPU, with two-Gb of RAM installed. I'm using Debian-Lenny that I've faithfully upgraded fortnightly via SMXI or APT-GET. Sometime in the past, with one of the kernel upgrades, SMXI switched over to installing the "pae" kernels.

Now, I know you are worried that some of the older CPU chips aren't compatible with "pae" and that you modified SMXI so as to not install a "pae" kernel whenever the computer doesn't have more than three or four GB of RAM.

But, it seems to me that if I "upgrade" to kernel 2.6.32-5-686 that I'm really downgrading. I can't find any way that I can use SMXI to upgrade the latest 3.2.0-4-686-pae kernel on my machine.

Is there a way to have SMXI look at a user's current kernel, and if they are already running a "pae" kernel to go ahead and allow further "pae" kernels to be installed? Or does the 2.6.32-5-686 kernel have all of the features of the 3.2.0-4-686-pae kernel, except the ability to use larger amounts of RAM?
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I believe the pae is the only difference. smxi does a few things, one of which is to check for pae compatibility via cpu flags, the other, as you note, is to check the actual size of the installed ram.

I thought smxi would also install by default the kernel you were running, but it's possible that pae update to smxi changed that. But there is as far as I am aware exactly zero advantage to using a pae kernel if you don't have more than 3.2 gB ram.
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So that's the test, it doesn't care what kernel you had installed. I think I was debating adding in a user flag they could set in smxi options to force pae but I opted against it given my understanding that there is no benefit to users to use pae kernels unless they need it.

If my understanding of this is flawed, then post an explanation of the error in understanding and I'll update smxi to handle user pae pre installed kernels. But I believe it's actually not desirable to run one if you don't need it.
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by the way, I wanted to let anyone reading this thread that the question is now moot, debian appears to have dropped support for non pae processors and 686, there is no longer any -686 kernel, only 686-pae

the regular 686 are now just dummy packages that pull in the pae, without, one might add, testing or otherwise confirming the system can run pae in the first place.

Not a very elegant switch, and certainly offers no help to people who run pentium M processors, which was at one point almost all ibm laptops.

I got caught with this one in smxi, which now will show an error message for your kernel selection if no non pae kernel is available yet you have a non pae cpu/mobo.

the null kernel handling was also improved.

Also, if the system is non pae, and if there is no non pae 686 kernel in debian, it will now use the 486, which will cover the pentium m case.
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