Which RedHat (32bit or 64bit) for Xeon?

Dan Pritts danno at internet2.edu
Wed Jul 13 15:05:59 CDT 2005


On Wed, Jul 13, 2005 at 02:49:03PM -0500, Matt Domsch wrote:
> > Red Hat Enterprise Linux ES (v. 4 for 32-bit x86)
> Would be fine.

> > Red Hat Enterprise Linux ES (v. 4 for AMD64/Intel EM64T)
> Would be fine.

But what advantages and disadvantages are there to one or
the other?

32-bit has binary compatibility with whatever binary distributions you
might choose to download.  Anything that's distributed as a 32-bit binary
might not work right with 64-bit mode (there are compatibility libraries,
but i know that in at least some cases that's not good enough).  

If you're running 32-bit everywhere else there might be manageability
reasons to stick with 32-bit here.

64-bit can address large amounts of memory much more efficiently than
32-bit can.  If you've got >4G definitely use 64-bit, 32-bit performance
goes down over 4G.  There are also issues with 32-bit systems' per
process address space - search for the 2G/2G split vs the 1G/3G split.
I don't know for sure but I presume this goes away with 64-bit.

danno



More information about the Linux-PowerEdge mailing list