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Many users and some OEMs are requesting the addition of a 32 bit PAE enabled kernel. Their reasons are thus:

• Almost all newer laptops can be purchased or upgraded to have more then 3GB of RAM.
• Many users prefer 32 bit user space in order to more easily use proprietary applications such as Skype and Flash.
• Existing 32 bit users want a 32 bit upgrade option.

The proposed kernel flavours for Karmic are as follows:

• i386-generic (no substantial change from Jaunty)
  • Should the minimum supported instruction set be CONFIG_M686=y? VIA C3, Transmeta Crusoe, and Geode LX are the most common non-Intel embedded x86 CPUs. All support the i686 instruction set (MMX, CMOV). Are there toolset issues with i586 and lower?
• i386-generic-pae (generic with PAE enabled)
• amd64-generic (no substantial change from Jaunty)
  • Is there enough reasons to continue to carry a separate flavour for the server? The process and I/O scheduler can be set at run-time. The biggest compile time option difference is CONFIG_PREEMPT_VOLUNTARY.
• lpia-lpia (no substantial change from Jaunty).
  • Need to think about the impact of true Moorestown support v.s. the i386/Atom approach that we've previously adopted for LPIA. Are there upgrade issues?
• armel-armv7 - compiling for v7 may force a number of the ARM SOCs to be dropped.
  • Is it still armel ?

Note that the i386-server flavour is being dropped. I can think of no good reason to continue to support a 32 bit server. The 32 bit -generic kernel ought to suffice for those headless implementations that have used the -server flavour in the past, such as home gateways. All of the -server unique settings can be made at runtime to a -generic{-pae} kernel, the most important of which are I/O and process scheduler settings.

A related Blueprint can be found at: https://blueprints.edge.launchpad.net/ubuntu/+spec/use-pae-when-possible