Concerns Over No PAE Kernel In Ubuntu 12.04 LTS
Phoronix: Concerns Over No PAE Kernel In Ubuntu 12.04 LTS
One of the fundamental kernel changes that was decided upon during the Ubuntu 12.04 Developer Summit by Canonical's kernel team is to drop support for the non-PAE 32-bit Linux kernel. However, it seems there is growing resistance towards this move...
Well that mean that a lot of Pentium M laptops will not work with Ubuntu too. I tried to use PAE on all of the i686 instruction set computers and that didn't workout. Turns out that several generations of the Pentium M does not support PAE at all.
Newer Ubuntu releases require instructions that older CPUs don't have (like AMD K6-2 series and older) so they won't work regardless. Nvidia drivers require SSE (fails with AMD Thunderbird for example).
Yup, this is the #1 reason to not do it. Pentium M systems are still viable today, even at 6-7 years of age.
Originally Posted by rapsure
People actually run default kernels? Why stress about this stuff when toggling one option and building a kernel takes less time than rebooting. Really, who cares.
Nobody should be worried. It's only Ubuntu. Those that need to move probably won't miss it, as there are dozens of great alternatives.
As pointed out, there are only a hand full of non-64bit capable machines out there that support >2GB, and even fewer of those machines actually contain >2GB. For those users of 32bit 3GB machines, they have the choice of downloading a more suitable distribution (Mint), or clicking a checkbox to enable PAE and recompiling. The down side of the latter is that it would put you into "unsupported" territory, which is fine for a technical user but bad if you have an enterprise with several hundred 32bit/3GB class Laptop PCs.
I would like to know what server class is going to be affected. For example, will the old pre-HP "Compaq DL-380" class of server be affected (I think they were the 3000 series)? IIRC, there are quite a few 32bit 4/8GB machines doing SMB and thriving in underfunded server rooms throughout the world.
Though I don't know why they did this and it seems to be another top-down decision being tossed out of the Canonical vacuum in the openwashed environment that UDS affords them, it doesn't mean that old processors that support PAE won't work.
Originally Posted by rapsure
All it does mean is that if you have one of these old processors, you will get a kernel which can't handle more than 4 GB of RAM. Since a lot of these laptops with the aforementioned Pentium M's came with Windows XP which had no PAE abilities, and most of them had far less than 4 GB of RAM anyway, this decision won't likely affect most users even if they have a laptop with a Pentium M.
Unlike Windows, with its arbitrary limitations, you can 1. Compile a kernel yourself with PAE support. 2. It's Ubuntu, there's probably going to be a PPA with a PAE kernel somewhere. 3. Use one for the hundreds of distributions that supports PAE if you have one of the rare 32-bit only processors that happens to support PAE, and more than 4 GB of RAM. That is an oddball combination though...
My guess is <0.5% of Ubuntu users will even be affected by this.
Likely, the Ubuntu kernel team came to the same conclusion and decided that maintaining an entire set of kernel packages for a handful of Ubuntu users wasn't worth it when in most cases, they can use a non-PAE kernel and not notice any difference. (But I don't think a PAE kernel will work on a non-PAE CPU, so dropping the standard 32-bit kernel for a PAE version would have affected most people still using obsolete 32-bit x86 processors.)
Edit: But I can almost hear you screaming about Atom processors, which I like to call CPU: Starter Edition since they are extremely slow and crippled much like the Windows Starter Edition they come with. Few of them ever shipped with more than 1-2 GB of RAM since XP Starter had an arbitrary 1 GB limit where Vista7 Starter has an arbitrary 2 GB limit.
Last edited by DaemonFC; 11-09-2011 at 09:10 PM.
In addition: Of the few 4GB capable Atom boxes that shipped, most of them can only address 3GB
Originally Posted by DaemonFC
256 --> Video memory.
512MB --> PCI hardware resources.
256MB --> PCI Express resources.
Last note is for the posters that seem to think that these machines "won't run Ubuntu". This is not true, and I'm not certain where this notion came from. Ubuntu will run just fine, but will be limited to 2GB. This is more than enough RAM to boot and compile/install a PAE kernel capable of recognizing the final 1GB.
Something tells me that owners of the "Aspire R3600" won't be interested in running Linux though.
And Mary Jane Walmartshopper who bought an eMachine with her alimony. What about her? (And her cats!?)
Originally Posted by russofris
They'll be heartbroken that Ubuntu doesn't support PAE, that is if they ever figure out what Ubuntu is.
PAE kernel works fine on CPUs without PAE support, so I cannot understand what's all the fuss about.