Blade server review: Dell, HP, IBM battle for the virtual data center

In addition to those tests, we rounded out the benchmarks by using Ixia's IxChariot tools to gauge network throughput between blades in the same chassis. Those tests were based on a few common loads, including iSCSI 32K and 256K read tests, a packet blaster load, and a BitTorrent P2P load that gauged connection rates. We also used Ixia's IxLoad testing tool to generate load on the LAMP application for preliminary testing, prior to using the benchmark's built-in client.

Westmere vs. Westmere
Although Dell, HP, and IBM were free to choose whichever CPU they liked for the test, all arrived with Intel Westmere-EP X5670 2.93GHz CPUs and at least 24GB of RAM in each blade. The reason for the Westmeres is clear: Six cores beats four, and with the Westmeres also edging Nehalem in per-core performance, they're the fastest thing going in the x64 world right now.

[ Fast AES encryption, better scalability, and consistent per-core performance make the new six-core Xeon a worthy successor to Nehalem. See "InfoWorld review: Intel's Westmere struts its stuff." ]

Dell also brought along one set of X5680 3.33GHz CPUs, which allowed us to see what the X5680 CPUs could do. For the sake of apples-to-apples comparisons, however, we evaluated the Dell blade's performance based on the X5670 chips. Our low-budget Supermicro blades were outfitted with slower (and far cheaper) AMD Opteron 2378s, quad-core Shanghai CPUs running at 2.4GHz.

We also allowed each vendor to choose which type of storage to bring. Dell showed up with a Dell EqualLogic PS6010XV 10G iSCSI SAN array, HP brought an EVA 2124 Fibre Channel array, and IBM also went the Fibre Channel route with a System Storage DS5020. Due to time constraints and the relative disparity between the storage mediums, SAN array throughput tests were not conducted.

The blade performance test results were quite interesting in that they were basically identical. Running the Westmere X5670s, the Dell, HP, and IBM blade solutions performed within the margin of error across all tests.

The threading concurrency tests showed that by and large, the Dell, HP, and IBM blades ran neck and neck, with IBM taking the slightest of leads near the upper end of the accuracy margin. The VMware LAMP application tests also resulted in a statistical draw, with IBM topping out at 2,125, HP at 2,110, and Dell at 2,104 requests per second, giving IBM a "lead" of around 0.7 percent. Suffice it to say, there's no significant performance difference among the three Westmere-equipped blade systems in the test.

Our low-budget Supermicro entry pulled in last, as expected. With four cores per CPU instead of six, a lower clock rate, only 8GB of RAM, and a chip that's several generations behind, the Supermicro performed quite well for its cost, but was nowhere near comparable to the Intel Westmere blades -- no surprises there.

Since Dell also brought a set of 3.33GHz Intel Westmere X5680 CPUs, we swapped those processors into one of the Dell blades and reran the threading concurrency tests. The results were around 12 percent faster than the X5670-based tests, reflecting the 400MHz increase in clock speed per core.

Interestingly, the Dell, HP, and IBM blades all performed equally well in the Ixia IxChariot throughput tests too. This shows that at this point in time, the major vendors have stabilized on Intel Westmere, and the internal 10G switching fabrics have matured. The Supermicro entry did not have 10G, but performed up to spec with the 1G interfaces present on the test blades.