I mentioned the update of the 7410 hardware in a blog entry yesterday afternoon. Brendan wrote an interesting blog entry about the performance impact with "7410 hardware update, and analyzing the HyperTransport". For cached workloads (to get the disks out of the equation), the increase of performance is really impressive:

Workload7410 (Barcelona)7410 (Istanbul)Improvement NFSv3 streaming cached read 2.15 Gbytes/sec 2.68 Gbytes/sec 25% NFSv3 8k read ops/sec127,143223,96975%
What many people forget when talking about Istanbul, is the fact that it didn't get just two additional cores. You get HT3 and HT Assist (a snoop filter to reduce bus contention by processors searching their data in other processors caches) with it. Brendan summarized his findings with:
For this 7410 upgrade, the extra CPU cores help - but it's more about the upgrade to the HyperTransport. HT3 provides 3x the CPU interconnect bandwidth, and dramatically improves the delivered performance of the 7410: from 25% to 75%.
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