Dual Core vs. Dual Processor for Servers

[chconline Veteran]

I've been digging up and down the net, and couldn't find much information. Some indicates that a dual core is better than dual processor for desktop environments in some cases, but how about servers?

For example, what will perform better in a server environment (Lets say, running several game servers): Dual core Opteron or Dual Opteron? Will there be a significant increase in performance for a Dual opteron, if any?

Any help is appreciated (Y) :)

[Vice]

Generally Dual Core will beat a Dual Processor configuration, the reason is quite simple memory bandwidth. By having both AMD Cores on 1 die within the processor they can communicate on a much faster and lower latency bus than using conventional Hyper Transport links through the motherboard. When you use 2 individual processors on an AMD Opteron dual socket board there is a 3rd HT link created between the 2 processors. But this is still slower and less responsive then having both cores sitting next to each-other.

[chconline Veteran]

Yeah that's mostly the information I got. Thanks anyway :) Will the shared cache be any big performance hit? I've read loads on desktop configs, and I only tried/have dual core comps around here but never actually used it for game server purposes :D

I read this review http://www.tomshardware.com/2005/11/07/single/index.html and some other article that was digged a while back, they PC marked and 3D marked it and the dual core came out top or equaled the dual cpu config. Just still no info on game server environments.

Anyone got any more info?

[Vice]

Well it really depends on the game. If your running CS:S DOD:S UT2004 or a BF2 server it will only utilise 1 core. And thus the practicality of having 2 processor cores (Either by using a Dual Core or just 2 individual processors) becomes worthless.

F.E.A.R. Ghost Recon and a few other games can however utilise both Cores (or more) and that is where the Dual Core processor will edge out it's single cored bredrin in a Dual Socket Configuration.

And by the way, the Opteron's do not share a L2 cache, each Core has it's own 512kb or 1MB L2 cache, they share data through the integrated memory controller. Which is exactly what gives it the speed edge over a Dual Socket Configuration which uses a Hyper Transport link.

[chconline Veteran]

Yeah, thanks :D Me and a few friends want to get a server for some game server purposes, so running several servers will really benefit from multi processor / multi core machines.

[Vice]

if you're going the Opteron route (Which I assume you are from above) might I suggest getting 2x265 Opteron processors they are 1.8GHz / 1MB L2 / Dual Core each and when you have 2 of them that's 4 physical cores purring together that with 4GB of RAM and it's a very fast and generous setup I think it would suit your server needs nicely.

[Blazkowicz]

with two separate AMD64 processors you have more RAM bandwith though. Tasks that like RAM bandwith may run better.

but in the end differences don't amount to much. Dual core (and soon quad core) is cheaper, not only in physical costs, but often for licensing too, some commercial server software is priced as $$$ by CPU and is thus twice the cost for n single core CPUs versus n/2 dual core CPUs.

[Japlabot]

I would get Dual Core on a Dual Processor board, so that you could upgrade to 2x Dual Core in the future.

[darkmark327]

Dual core also has the advantage that many more expensive programs which have per-processor licensing do so per-package and not per-core. So a dual processor machine would be charged more than a dual-core.

[Blazkowicz]

  Quick Reply said:

I would get Dual Core on a Dual Processor board, so that you could upgrade to 2x Dual Core in the future.

that sounds good, but you're paying a high price for that.

let's talk AMD : instead of getting a cheap mobo, an X2 3800+ and standard DDR2 you're getting an expensive two sockets mobo (socket 940 or F), an expensive Opteron 2xx or 22xx, and very expensive registered RAM.

The future will also bring us quad core CPU on a single socket, and AMD 4x4 which is just like opteron two 265 but with cheaper, standard RAM.

[Echilon]

I'd go for dual processor, because each CPU will have dedicated memory.