Yesterday, I posted about the architectural choices made at the software level, and the results of some of the benchmarking that was done prior to launch. A couple readers pointed out that I didn’t mention what sort of hardware we’re running.

The benchmarks from yesterday covered one of our web nodes, a Sun X2200 M2. This is Sun’s 1-4 way 1U Opteron server, which gives us good density and power efficiency. Our web nodes are 4-way 1.8ghz affairs, with 4G RAM and a simple RAID-1 for reliability. The load balancers are 2-way with 2G RAM, same processors. Each of our database servers is an IBM x3655 Opteron server, 2U, with a six-drive 15k SAS RAID 10. These are 4-way 2.6ghz boxes with 8G RAM.

You’ll notice the web nodes are fairly low speed per-core. This makes the most sense to us, since it keeps us power efficient. We’re very confident about our ability to respond quick enough per request, so we instead go wide with the four processor solution. The databases do much of the heavy lifting in terms of our statistical algorithm, so they get the high performance CPUs, again, wide to handle many concurrent requests.

Thanks for the questions!