686-pae over 486 kernel

[Getafix]

I recently updated kernel on LMDE up7 to 3.10-2-686-pae after I read it is not recommended to run 486 as it does not support multi cores. Can we please discuss about the advantages of running a 686 pae kernel ? How much difference does it make than 486, and how can it help the most resource consuming processes like Cinnamon and Chromium, Firefox. And if there is any cons.

I hope this will be very helpful to all. Thanks.

[xenopeek]

Answered in the release notes of LMDE:

Multi-core and multi-CPU support in 32-bit kernel

To guarantee compatibility with non-PAE processors, the 32-bit versions of Linux Mint Debian come with a 486 kernel by default. This kernel does not support SMP, and as a consequence is only able to detect one core and one CPU. If your CPU has multiple cores, or if you have more than one CPU, simply install the 686-PAE kernel and reboot your computer.

Type the following commands and reboot the computer:

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apt update

apt install linux-headers-686-pae linux-image-686-pae

In other words, if you have a modern quad-core CPU you would be using only 1/4th of its potential with the 486 kernel. Note that all this applies to 32-bit installations of LMDE only!

[Getafix]

Hi Xenopeek. I switched to 686-pae kernel as said there. But Xorg fails to start every time I try to load the nvidia driver. There seems to be something missing. I used DDM to install that pae kernel before, and now again with apt-get install linux-headers-686-pae and apt-get install linux-image-686-pae

Here is the package information.

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fayad@lmd3-gnulinux ~ $ apt-cache policy linux-image-686-pae
linux-image-686-pae:
  Installed: (none)
  Candidate: 3.10+51
  Version table:
     3.10+51 0
        500 http://debian.linuxmint.com/latest/ testing/main i386 Packages
fayad@lmd3-gnulinux ~ $

fayad@lmd3-gnulinux ~ $ apt-cache policy linux-image-3.10-2-686-pae
linux-image-3.10-2-686-pae:
  Installed: 3.10.5-1
  Candidate: 3.10.5-1
  Version table:
 *** 3.10.5-1 0
        500 http://debian.linuxmint.com/latest/ testing/main i386 Packages
        100 /var/lib/dpkg/status
fayad@lmd3-gnulinux ~ $

Also my sources information.

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fayad@lmd3-gnulinux ~ $ inxi -Sr
System:    Host lmd3-gnulinux Kernel 3.10-2-486 i686 (32 bit) Distro LinuxMint 1 debian
Repos:     Active apt sources in file: /etc/apt/sources.list
           deb http://packages.linuxmint.com/ debian main upstream import
           deb http://debian.linuxmint.com/latest testing main contrib non-free
           deb http://debian.linuxmint.com/latest/security testing/updates main contrib non-free
           deb http://debian.linuxmint.com/latest/multimedia testing main non-free
fayad@lmd3-gnulinux ~ $

Edit: Forgot to mention the drivers. Tried nvidia-glx, nvidia 331.38 and 319.49. All failed to start xorg.

[killer de bug]

Have you read this? http://forums.linuxmint.com/viewtopic.php?f=191&t=82424

You need to configure graphic drivers with your new kernel.

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sudo nvidia-xconfig

[Getafix]

Have you read this? http://forums.linuxmint.com/viewtopic.php?f=191&t=82424

You need to configure graphic drivers with your new kernel.

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sudo nvidia-xconfig

Thanks for replying. I think I am installing the driver correctly and nvidia-xconfig is run. Here is the deal. The drivers load fine with 3.10.4-486 kernel and also 3.2-0.4. So drivers are fine. The 686 pae kernel is just not able to load the nvidia driver. Xorg.conf is properly placed, I tested by keeping it both in /etc/X11 and /etc/X11/xorg.conf.d.

Maybe something I missed when installing the new kernel ?

[Monsta]

I found this package, maybe that's what is needed for your new PAE kernel?

[killer de bug]

This package is for 3.12 kernel...

[Monsta]

That's a metapackage that depends on nvidia-kernel-<version>-686-pae. So in UP7 it would depend on nvidia-kernel-3.10-2-686-pae, I think.

[Getafix]

This package is for 3.12 kernel...

There is its equivalent package for 3.2.0-4-686-pae. I will install this kernel and load the driver to see how it goes.

Interesting thing is, I couldn't find 3.10-2-686-pae in wheezy stable but only 3.2.0-4-686 and 3.12.

[killer de bug]

Interesting thing is, I couldn't find 3.10-2-686-pae in wheezy stable but only 3.2.0-4-686 and 3.12.

Wheezy was freezed with 3.2. Then 3.9 3.10 3.11 and 3.12 have been backported. http://packages.debian.org/wheezy-backp ... .3-686-pae
http://packages.debian.org/wheezy-backp ... .2-686-pae http://packages.debian.org/wheezy-backp ... .1-686-pae

[Getafix]

Thanks Killer and Monsta for the support.

It looks good now. Nvidia driver 319.49 is loaded with 3.2.0-4-686-pae and all cores are identified. So I can be happy with that, unless there is something to worry about 3.2.0-4-686.

That was by adding Debian wheezy stable repository to sources and did a apt-get install linux-image-3.2.0-4-686-pae. That's it.

I also looked at `nvidia-kernel-3.2.0-4-686-pae`. That's supported for 304.88 nvidia driver so that has not come into action now. I think that can be a required package if running nvidia-glx.

Before I wind up that brings some doubts to mind. Firstly, I have now deb http://packages.linuxmint.com/ debian main upstream import and also the newly added deb http://ftp.fr.debian.org/debian wheezy main in sources.lst. If I am right packages.linuxmint.com has debian and its main repository enabled which is wheezy. So there is not much use in adding that new repository unless there is a package available in it which isn't available in packages.linuxmint.com. Secondly, in case of a package being available in more than one repo, the one that comes first in sources.lst will be considered. Am I right here ?

[killer de bug]

It looks good now. Nvidia driver 319.49 is loaded with 3.2.0-4-686-pae and all cores are identified. So I can be happy with that, unless there is something to worry about 3.2.0-4-686.

Now that you know how to do it, you may be interested by a newer kernel. I have alway found 3.2 to be buggy with Nvidia. I had some freeze with suspend/resume.

If I am right packages.linuxmint.com has debian and its main repository enabled which is wheezy.

LMDE is based on Testing. Currently Testing is Jessie. Wheezy is stable.

So there is not much use in adding that new repository unless there is a package available in it which isn't available in packages.linuxmint.com.

packages.linuxmint.com is only for Mint specific software (Cinnamon, Nemo...). But the other repo of Mint are more up to date than wheezy since they are based on Testing. So you don't need stable repo

Secondly, in case of a package being available in more than one repo, the one that comes first in sources.lst will be considered. Am I right here ?

Wrong. It depends on your preferences file. https://wiki.debian.org/AptPreferences# ... references

[Getafix]

Perfect. Thank you Killer de bug.

Now that you know how to do it, you may be interested by a newer kernel. I have alway found 3.2 to be buggy with Nvidia. I had some freeze with suspend/resume.

And which kernel did you move to for suspend/resume feature ? And the graphics driver.

[killer de bug]

With testing and UP we got Kernel 3.10 and currently 3.11.
3.11 is really good in my opinion

[Getafix]

With testing and UP we got Kernel 3.10 and currently 3.11.
3.11 is really good in my opinion

Thanks again I am testing 3.11-2-686-pae that's available in linux mint repository. It works fine, there is one problem though. Sometimes booting stops at "Loading please wait" after the grub menu and system freezes. I am facing this often now. In my grub.cfg I have

linux /boot/vmlinuz-3.11-2-686-pae root=UUID=5e7321e2-0411-433b-a452-9c74b8e200e6 ro quiet

UUID is correct. No errors found in dmesg.

[Getafix]

Well its time to move to UP 8. Great work by the LMDE team.

http://blog.linuxmint.com/?p=2544

[Getafix]

I still have that occasional freeze during boot. It hangs just before Loading kernel please wait. There is nothing helpful from the logs because it happens right when booting begins, so I am stuck. I updated to UP 8 and it has kernel 3.11-2-686 (I had already updated to that kernel before moving to up 8 )

lmd3-gnulinux ~ $ uname -a
Linux lmd3-gnulinux 3.11-2-686-pae #1 SMP Debian 3.11.8-1 (2013-11-13) i686 GNU/Linux
lmd3-gnulinux ~ $