[CIG-MC] CitcomS and Intel Xeon E5-2600 processors

[Max Rudolph]

Dear All,
I'm getting ready to buy some computer equipment and I'm wondering
whether anyone has experience running CitcomS on the recenty-released
higher core-count Intel Xeon E5-2600 v3 series processors (or their v2
predecessors), specifically the 12-core chips. The 12-core CPUs can
run 24 threads (i.e. MPI processes) efficiently, so in principle it
seems like dual 12-core Xeons would make for a very cost effective
computer to do small 3D calculations, post processing, etc. A system
with 2 of these processors and 128 GB RAM goes for around $7500 right
now. My question though is whether the memory bandwidth is going to be
too much of a limitation to make this a worthwhile alternative to
buying more nodes with fewer cores per node. The per-core memory
bandwidth (2x 8.0 GT/s QPI links per cpu) is somewhat higher for the
8-core cpus than for the 12-core cpus (2x 9.6 GT/s QPI), so if memory
bandwidth is the limiting factor, it may be a wiser decision to go
with more nodes at reduced core count. Any input would be much
appreciated.

Regards,
Max Rudolph