do I need to do something special to use more than 4 Gigs under Feisty?

[Gavin McCullagh]

Hi,

On Thu, 31 May 2007, john  wrote:

> I appreciate that info. I am thinking about that approach as well. I have
> some concerns that the 64bit kernel isn't as stable as the 32 bit kernel,
> do you have any opinions, or places you could point me to research that?

I'm not sure my opinions would count for much but here's what I'm aware of
in this realm:

 - The linux kernel itself has been tested and in use on various 64-Bit
   architectures for many years now (Sparc64, Alpha, IA-64, etc.) so it's
   not as though an effort to port to 64-Bit started last year or anything.

 - On the other hand, most servers and desktops are still 32-Bit so that
   combination is undoubtedly better tested.

 - If you're going to be using >4GB RAM by PAE, you're probably charting
   slightly less tested territory there anyway.

 - My own desktop runs very stabley with 64-bit linux.  I had a problem
   with booting after a recent kernel upgrade but it turned out I needed to
   boot with the noapic option

 - I've no idea how well flash/java work in 32-bit mode on 64-bit machines.
   I haven't bothered to do this myself.  GNASH is not a viable replacement
   yet.

As I understand it, the linux kernel is pretty stable on 64-Bit systems
(perhaps some particular machine might be an exception, but that's true in
32-Bit too).  The problem really seems more to be application support and
perhaps some drivers.

Performance appears to be similar between the two -- though using 8GB RAM
might give the 64-Bit an edge.

http://www.phoronix.com/scan.php?page=article&item=616&num=1

Gavin