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Re: Debian Gnome Or XFCE ?



On Sat, 15 Aug 2015 06:28:53 -0400 (EDT), Bret Busby wrote:
> 
> On 15/08/2015, Stephen Powell <zlinuxman@wowway.com> wrote:
>> ...
>> My IBM ThinkPad X31 laptop, which is still quite usable,
>> would be a brick if I ran Ubuntu.  It has a Pentium M
>> processor in it, and that processor does not have the PAE
>> feature.
> ...
> a solution to the PAE problem, relating to your Pentium M CPU, was
> mentioned, if you would be bothered to do anything about that.
> ...

I don't wish to "stir the pot" again; but when I make a mistake,
I need to correct it.  You are right, Mr. Busby.

The IBM ThinkPad X31 laptop which I possess contains a Pentium M
processor which *does* support PAE but does not *advertise* that it
supports PAE.  Therefore, a PAE-requiring Linux kernel *will* run
successfully on this processor if the "forcepae" kernel boot parameter
is passed.  Therefore, I was wrong when I said that this laptop
would be a "brick" if I were running Ubuntu.

However, there are 32-bit Intel-compatible processors out there which
neither advertise nor possess PAE capabilities.  Therefore, a non-PAE
kernel is still needed for them.  Furtherfore, a non-PAE kernel is
useful even on PAE-capable hardware.  The main purpose of PAE is to
address memory above 4G.  But if the machine has less than 4G of
memory, what does a PAE-capable kernel buy you?  PAE-capable kernels
tend to be a bit bigger, all other things being equal, than non-PAE
kernels, which chews up more precious memory with no obvious benefit.

Furthermore, use of the "forcepae" option to force a PAE kernel to run
on a processor which supports PAE but does not advertise such support
has drawbacks.  It taints the kernel, which disables lock debugging,
for example.  For these reasons, I believe that a non-PAE kernel is
still needed; and I applaud Debian for providing one.

Respectfully,

-- 
  .''`.     Stephen Powell    <zlinuxman@wowway.com>
 : :'  :
 `. `'`
   `-


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