[nflug] AMD64 Debian 'Etch' Stability

Ken Smith kensmith at cse.Buffalo.EDU
Fri May 23 09:20:11 EDT 2008

On Fri, 2008-05-23 at 08:26 -0400, Robert Wolfe wrote:
> Good morning all!
> I was wondering what some folks' thoughts were on the stability of the
> AMD64 version of Debian Etch are?  I have been wanting to push the use
> of the 64-bit version on our higher-end servers here at work (have a
> bunch of new AMD64-based servers that have dual quad-core Xeons in
> them with 16GB of RAM that act as our VMWare Server servers).  I know
> of at least one person that claims that the 64-bit version of Debian
> is not stable enough to run as a server OS. 
> Could someone confirm or not whether this is true?
> Thanks!

I can't confirm or deny your specific question (specifically Debian) but
I've worked with lots of different systems with respect to the general
question (32-bit versus 64-bit) and the general trend has been the same
amongst the huge majority of the systems I've worked with so far.

The general trend is that the baseline OS's these days are *typically*
past the point of having big problems with 64-bit related issues.
They've been working with 64-bit hardware for quite a while now and in
different variants (sparc64, etc...) so most of the bugs have been
ironed out there.

The applications are another story... :-/  Most people see stuff fail on
64-bit machines and blame the base OS but it's really the fault of the
application(s) themselves.  Some OSs don't "help" in that regard by
trying to be too helpful...  :-)  Often times they'll try to support
running 32-bit binaries on 64-bit platforms as a means to make more
stuff work but then you need to be very very very careful with how you
build things, update things, etc. - the 32-bit libraries are separate
from the 64-bit libraries for example; you can't mix 32-bit libraries
with 64-bit libraries, etc. etc. etc...

I get asked the question of "Should I do 64-bit or 32-bit?" a lot.

Before the FreeBSD 7.0 release my advice had been to NOT use 64-bit on a
workstation because too many of the applications people expect to use in
that sort of an environment were still suffering from 64-bit issues (or
didn't exist at all) and using 32-bit executables on a 64-bit system was
possible but difficult to pull off seamlessly (e.g. you typically found
yourself needing to use 32-bit Web browsers since the plug-ins people
wanted the most were 32-bit and ...).  For server systems my advice had
been to thoroughly test the applications you needed on the server, and
if they worked then go for it.  Process sizes on 64-bit will typically
grow since pointers are larger, etc. but using larger than 4Gb of RAM on
a 32-bit machine involves some fiddling around in the OS that impacts
performance a little bit, process sizes themselves are still limited
despite the OS being able to manage more than 4Gb RAM, etc...  And as we
all know stuff never gets smaller over time so if you're installing new
machines at this point and expect them to be usable for 4 to 5 years (or
more...) it's time to at least start seriously considering 64-bit for
situations you can get away with it now...

As of FreeBSD 7.0 the majority of people should probably still stick to
32-bit on workstations but if you don't wander too far into "exotic
stuff" (mostly the multimedia type stuff...) it's at least possible to
use a 64-bit system on a workstation.  Both my office machine and home
machine are running 64-bit and I don't run into too much stuff I
desperately need that doesn't work.  The baseline windowing goop
(Gnome/KDE) seem to work just fine.  I don't have Flash working yet but
sometimes I consider that a benefit... :-)  Opera is just now working on
a FreeBSD 64-bit version so I need to use their development downloads
for that, it's not "production" quite yet.

You're likely to see exactly the same sort of situation for Debian...
Most of the Linux systems here in the Department are RedHat and I see
the same trends there.  We've chosen to go mostly 64-bit but for example
our firefox executable is 32-bit because of plug-in issues, etc...

                                                Ken Smith
- From there to here, from here to      |       kensmith at cse.buffalo.edu
  there, funny things are everywhere.   |
                      - Theodore Geisel |

More information about the nflug mailing list