I would like to know more on choosing hardware to get the maximum price/performance when using the PETSc library (and various third-party preconditionners)
I am currently working on a 2 cpu (2*E5-2640) workstation with a total of 24 logical cores. But my system is bounded by RAM banwidth such that I don't get any speed-up with more than six cores (even on a large problem). I get such results both on my apps and with the included benchmark.
Since some of my colleagues are in the process of buying hardware in the order or 100 cores, I would like to know how hardware should be chosen in order to get better memory bandiwidth.