bw lat(near cpu) lat(far cpu) -------------------------------------------------- QDR 3300* 1.12 1.54 FDR 6000 0.85 1.59
thanks for the numbers, though they are somewhat perplexing.
QDR hw is mlx connectx3 to mlx switchX (same switch), ivy bridge node. FDR hw is mlx connectx3 to mlx switchX (same switch), sandy bridge node.
hmm, so do you have an sense for what differences are due to host differences? also, what does near/far mean if this is all on the same switch? (simple 36pt switch, or is it a big switch with an internal fat tree?)
Of course what people refer to as QDR could also be connectx2 or qlogic/intel. The smaller hit for "far cpu" for qdr could in my case be an improvment from snb to ivb.
that kinda makes it sound like near/far is just the in-node topology (far means +1 QPI hop?) thanks, mark hahn. _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf