I currently run a couple of forum-heavy websites on a Pentium D950 (3.4 GHz 800FSB Dual Core 2x2mb cache). The sites use most resources for mysql and php (via apache), plus some more for email and serving images via tux.
So now I'm looking for an upgrade. I've grabbed the following off the Softlayer website:
Server CPU Speed CPU MHz CPU Cache Price
Intel Xeon 5050 2 x 3.00GHz 667MHz 2 x 2MB - HT $179
Intel Xeon 5130 2 x 2.00GHz 1333MHz 1 x 4MB $199
Intel Xeon 5140 2 x 2.33GHz 1333MHz 1 x 4MB $239
Intel Xeon 5160 2 x 3.00GHz 1333MHz 1 x 4MB $279
Intel Xeon 5310 4 x 1.60GHz 1066MHz 1 x 8MB $219
Intel Xeon 5320 4 x 1.86GHz 1066MHz 1 x 8MB $259
Now what do I make of this? First of all, I'm having a hard time relating the CPU speed to the clock speed. The 5050 seems alright to me, but I've read somewhere that Dempseys are already regarded as outdated, so obviously I'm underestimating the importance of clock speed? (Do I get the performance by basically multiplying the clock speed with the CPU speed?) Also, what's up with the quad core? Is that something worth considering for the purpose mentioned above, or will it be wasted on the four cores? What about the lower CPU speed of the quad core - will the faster dual core actually get the same or even more work done?
Or am I looking at the wrong brides and should rather run and get myself two cheapo servers with php on one and mysql on the other? (Or go with one of the above and just take two disks?)
Soooo many questions, I know. Hoping for a couple of decent responses as well - thanks in advance!
The Xeon 5000 series should be considered old. It was released prior to 2006, and it has already been outdated twice by new Xeon releases including the 5100 dual-cores and the 5300 quad-core chips.
Moving from the Pentium D to the Xeon 5100 or 5300 will give you a significant performance gain due to the faster frontside bus, larger and more available cache (in the 5100, it's 4MB L2 for all four cores whereas in the 5300 it's 4MB per core pair for a total of 8MB).
The quad-core will out-perform the dual-core CPU because of how your software runs. Both Apache and MySQL are threaded. Focusing on Apache, let's assume you use the threaded worker MPM and receive 65 requests per second. That's 65 threads per second, and you'll probably have upwards of 256 threads being processed at once. Which would you prefer: The threads being handled by four cores (dual cpu) or the threads behing handled by eight cores (dual cpu)?
While the 5300's are slower, they are overall faster than the 5100. A dual CPU Xeon 5160 system is 12Ghz. A dual CPU Xeon 5310 is 13.28 Ghz. That's the best 5100 vs the worst 5300. Now, granted, the 5310 won't process as fast as the 5160, but it will still out-perform most of the equivilant (in price) 5100s.
While I haven't used Pentium D in any servers, yet, I can give you an example of performance gains based on a similar gap in technology.
I recently purchased a new database server. The server prior to this one was a Dual Xeon 3.2 Ghz with HyperThreading and only single cores. The power of this server could probably chirp with some of the faster Pentium D's. This old server had an average load of 20 at peak time. The new server was a dual Intel Xeon 5160 - 3.0 Ghz, dual-core. The load on this box at peak is 2. Chances are, if I were to use a Xeon E5335, for example, I'd match the power of the 5160.
Here's the breakdown:
1. The Xeon 5000 is out-dated by two generations and should not be considered if you want near-new or new equipment.
2. The Xeon 5100 is a very decent choice using a proven CPU.
3. The Xeon 5300 is the better choice if you only care about power and cores; however, it is a brand new line of chips and has not proven to be stable (yet). Furthermore, being as new as it is, you'll see a premium hike in price that will drop in the coming months. If you buy it now, you'll only be spending more money due to impatience.
One sidenote, however, is that in the list of CPU's you showed, it only lists the two slowest Xeon 5300s. If those are you two only choices, go with the 5100 line of 1333Mhz FSB chips. You won't regret it.