Kernel 3.2 686: Mouse broken

[justwill]

Hi all,

Relatively new to linux here. I searched the forum and didn't turn up anything useful, so here goes.

I recently updated through UP 4, and I noticed that it upgrades the kernel to 486. Because I have a processor with two cores, I went ahead and installed the 686-pae version of the kernel through Synaptic. I rebooted into 3.2 686-pae, and my mouse stopped working! The cursor appeared on the screen, but would not register any movement.

I rebooted into 3.0 686, and the mouse worked fine again. So I started poking around, and then I realized that I hadn't installed the headers for 3.2 686, so I went ahead and installed those through synaptic. I rebooted into 3.2 686, and voila, the mouse works again. I turned off my computer for the day, thinking I had solved the problem.

When I turned on my computer today and booted into 3.2 686 pae, the mouse had stopped working again. I ran lsusb in the terminal, and my mouse showed up.

Any ideas? I'm using a logitech m570 wireless trackball, which worked just dandy til now.

The weird thing is that my mouse works just fine in the 486 version of the kernel.

A brief recap:

1. Mouse works fine in 3.0 686, 3.2 486.
2. Mouse broken in 3.2 686
3. Installed headers for 3.2 686, rebooted into 3.2 686, mouse works fine. Shut the computer off.
4. Boot into 3.2 686 and mouse broken.

Help?

Justin

Edit: Reopening, because it's having trouble again.

[Oscar799]

Moved here by moderator

[justwill]

For whatever reason, it's solved. Booted into 3.2.0.2-686 and mouse works fine. Go figure.

[badmofo12345]

I don't know how to fix your mouse (or how it was automatically fixed), but I just want to help you out with some stuff that you seem confused about.

1) There was no problem with having a "486" kernel installed. Oftentimes, kernels are named i386, i486, i686, etc, basically just to let you know the earliest platform it was made for. They are all examples of 32-bit kernels, and have absolutely nothing to do with number of processors or cores. For example, I have an old Pentium 4 w/ HT Thinkpad laying around somewhere running an old 2.6 era i386 kernel, and multicore processing works just fine on it... An i386 kernel would have ran just fine on a Core i7, for example, just as it would (theoretically) run fine on an old 80386 system. An i486 kernel would have ran just fine on a Core i7, or an old 80486 system, but NOT on an old 80386 system... etc...

2) i686 PAE has nothing to do with multiple processors or cores... PAE is simply Physical Address Extension. A PAE kernel allows your system to use more than ~3 gigs of ram on a 32-bit system. A standard 32-bit system will only address around 3-4GB or RAM... PAE adds support for larger amounts of RAM (up to 64GB) without installing a 64-bit kernel.

3) For performance reasons, if you want to address more than 4GB of RAM, and you have a 64-bit processor (you probably do... I can't think of any current multicore processors that aren't 64-bit), you should definitely install an x86-64 (or amd64, depending on what your distro calls it) kernel. IMPORTANT NOTE: IA-64 is NOT what you are looking for... it's a 64-bit kernel specifically for Itanium 64-bit servers... An amd64 kernel will outperform a 32-bit kernel on similar hardware. It also allows an insane amount (more than you'll ever need) of RAM to be addressed. Don't let the amd64 name fool you, it is the same kernel that you'd want to install on an Intel 64-bit system too...

http://www.phoronix.com/scan.php?page=a ... ae64&num=1

TL;DR version:
i686-PAE doesn't have anything to do with multicore processors.
If you really wanted to maximize performance, you should install an x86_64 kernel instead, as a 32-bit PAE kernel will probably not net you any type of performance boost.
x86_64 (amd64) > 32-bit PAE (i686-PAE) > 32-bit (i386, i486, i686, etc...)


I think you might be getting SMP confused with PAE...

[justwill]

Thanks for the reply.

1) I guess I'm confused. I initially installed the 686-pae version of the kernel because the LMDE install instructions, on their website, said that I would need to if I wanted to take advantage of multiple cores. While I can't find where I got that info, the description of the 486 version of the kernel says this:

"This kernel is not suitable for SMP (multi-processor, multi-core or hyper-threaded) systems."

This seems backed up by the system monitor, which recognizes one processor in the 486 kernel, but multiple processors in the 686 pae kernel. Am I doing something wrong?

2) The mouse stopped working again! I don't know what's going on! Any ideas? Anybody else having this problem?

[justwill]

Anybody?