On Fri, Jan 27, 2012 at 06:10:02PM -0800, Bill Broadley wrote: > Anyone have an estimate on how much latency a direct connect to QPI > would save vs pci-e?
~ 0.2us. Remember that the first 2 generations of InfiniPath were both SDR: one for HyperTransport and one for PCIe. The difference was 0.3us back then; PathScale + QLogic did some heroic things since to shorten the pipeline stages & up the clock rate. -- greg (and if anyone needs a reminder, I no longer have any financial involvement with QLogic or Intel.) _______________________________________________ Beowulf mailing list, [email protected] sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
