Here's the question: is there any benefit to having dual-processor machines on any of these? I think we can afford 3 of them, if necessary, but is it even needed? I was planning on going with Dual-Xeon 2.8 GHz boxes running Linux. I'd rather not run more than one instance of Zope on the clients, btw.
Even if Python threads *loved* multiple processors, I usually find SMP to be less than optimal. You can do the math for yourself when you get your quotes, remembering that two processors will compute significantly below 200% of a single processor no matter what you do. My strategy: Get a good solid server for your ZEO server. Run the ZEO client on this one too, and see if you can get away with it. If not, add cheapo web servers with ZEO clients until you're comfortable with the load. If you're clever, these might not even need disks. (See Knoppix.) Sure, they aren't serious machines, and they might fail. But who cares? You have bunches of them! If you run Zope on a mulitple processor system, run one ZEO client per processor, and set processor affinity if you can. (Solaris can, and so can newer Linux kernels .) You may not like this much, but it's not so bad if you use zopectl or something like it. And remember, Zope will benefit a LOT more from extra memory than from extra processors. --jcc -- "My point and period will be throughly wrought, Or well or ill, as this day's battle's fought."