Re: hardware advice

On Sep 28, 2012, at 1:20 AM, Shaun Thomas <sthomas(at)optionshouse(dot)com> wrote:

> On 09/27/2012 04:08 PM, Evgeny Shishkin wrote:
>
>> from benchmarking on my r/o in memory database, i can tell that 9.1
>> on x5650 is faster than 9.2 on e2440.
>
> How did you run those benchmarks? I find that incredibly hard to believe. Not only does 9.2 scale *much* better than 9.1, but the E5-2440 is a 15MB cache Sandy Bridge, as opposed to a 12MB cache Nehalem. Despite the slightly lower clock speed, you should have much better performance with 9.2 on the 2440.
>
> I know one thing you might want to check is to make sure both servers have turbo mode enabled, and power savings turned off for all CPUs. Check the BIOS for the CPU settings, because some motherboards and vendors have different defaults. I know we got inconsistent and much worse performance until we made those two changes on our HP systems.
>
> We use pgbench for benchmarking, so there's not anything I can really send you. :)

Yes, on pgbench utilising cpu to 80-90% e2660 is better, it goes to 140k ro tps, so scalability is very very good.
But i talk about real oltp ro query. Single threaded. And cpu clock was real winner.