On Thu, Oct 09, 2003 at 10:41:29AM -0500, Jimmie Houchin wrote:
> Current configuration is a dual Opteron with a SATA RAID of 4 250gb
> drives with 4gb RAM. I am hoping to run Gentoo or Debian.

Well, I'm jealous. :-)

> I am not experienced in this.
>
> Will Apache 2.0.47, SCGI, Quixote, MySQL be able to effectively utilize
> the 4gb of RAM? Or am I getting more RAM than will utilized.

Hard to say since you didn't give any information on what kind of
site you will be running.  Quixote does like lots of memory.  That
said, modern machines have massive amounts of memory as compared to
a few years ago.  Our largest application is currently using about
200 MB of memory on a dual Athon XP machine.  The database server
(ZEO), also running on the same machine, is using about 45 MB.

We've got a few more Quixote applications running on that server and
here's what "free" says:

               total       used       free     shared    buffers cached
  Mem:       2069164    1824324     244840          0     249096 1008128
  -/+ buffers/cache:     567100    1502064
  Swap:      1959672      77812    1881860

> I know, not enough data on my app, etc.

Right.  Also, make sure to account for the fact that Opteron is a
64-bit architecture.  I think you can expect to need about twice as
much memory as an IA32 machine (unless you are using 32-bit mode),
due to larger pointers, ints, and data alignment padding.

BTW, I've been looking at the Opteron and the Athon 64.  The
reduction in memory latency is impressive (due to the on-chip memory
controller I understand).  I think that could significantly improve
Python performance since Python does an insane amount of "pointer
chasing".

> Naively, I think so, but want to run it past more experienced folks.

My guess is that 4 GB should be plenty.  2 GB would probably suffice
but I would go with 4 if you have the budget.

  Neil