Dropping i386 non-PAE as a supported kernel flavour in Precise Pangolin

Steve Langasek steve.langasek at ubuntu.com
Tue Nov 15 02:14:17 UTC 2011

Hi Tim,

On Wed, Nov 09, 2011 at 02:43:28PM -0700, Tim Gardner wrote:
> Per discussion at UDS the kernel team is proposing to drop the
> non-PAE i386 flavour. The upgrade path for non-PAE users will be the
> PAE kernel. Those CPUs that do not have i686 and PAE support will be
> orphaned. To the best of my knowledge, these include Intel CPUs
> prior to Pentium II, 400Mhz Pentium M, VIA C3, and Geode LX. As far
> as I know, there are no laptop or desktop class CPUs being produced
> that do not meet these minimum requirements.

> Before I do something that is difficult to revert, I would like to
> hear from the development community why we should continue to
> maintain a kernel flavour that is (in my opinion) getting
> increasingly low utilization. It is my feeling that an extremely
> high percentage of users of the non-PAE kernel have a CPU that is
> PAE capable.

> If there is sufficient community demand (and support), I would be
> willing to sponsor the first non-PAE kernel upload to Universe.

As I mentioned to you at UDS, I think this is the wrong way to go about
keeping the non-PAE kernel.  *IF* we are going to keep it, it's much more
efficient to build this as an additional, universe-only flavor from the main
source package.  Yes, this would occasionally mean additional work on the
part of the kernel team to keep the config up to date; but the alternative
is that a lot more work would have to be done to manually keep the non-PAE
kernel flavor in sync (syncing git trees, uploading multiple source
packages, archive processing of separate uploads for security updates).

If we're going to do this, let's please do it the right way, from a single
source package that only needs to be updated once.

If continuing to build this from the linux package is a significant
maintenance burden for the kernel team, that's certainly a factor to
consider in deciding whether to drop the package; but I don't understand how
that should be as the delta between the pae and non-pae packages should be
minimal, stable, and require no ongoing manual effort.  If maintaining this
flavor is actively consuming kernel team time, that seems like a fixable

I certainly agree that we should be delivering PAE to i386 users by default
these days, and I think it's fine to not provide support for installing on
non-PAE systems (which is implied by putting the non-PAE kernel to universe
and making PAE the default kernel in the installer images).  And I certainly
would not expect anyone to spend time supporting a PAE flavor for LTS
backported kernels, given that the purpose of LTS backports is enablement of
*new* hardware.  But unless people are just plain mistaken about what
hardware supports PAE or not, I think this thread is evidence that non-PAE
hardware is still relevant over the 12.04 support timeframe to a number of
our users and we should consider continuing this flavor for 12.04.

Steve Langasek                   Give me a lever long enough and a Free OS
Debian Developer                   to set it on, and I can move the world.
Ubuntu Developer                                    http://www.debian.org/
slangasek at ubuntu.com                                     vorlon at debian.org
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 828 bytes
Desc: Digital signature
URL: <https://lists.ubuntu.com/archives/kernel-team/attachments/20111114/82bda578/attachment.sig>

More information about the kernel-team mailing list