Reporting memory bandwidth in Gb is misleading.
The page you cite here: http://www.intel.com/content/www/us/en/benchmarks/server/xeo...
shows a triad bandwidth (STREAM) of 246,313.60 MB (megabytes) per second which is 240 GB (gigaBYTES) / sec.
If I'm making a mistake I'm sure we can work it out.
Re:Google's POWER8 server motherboard
by justincormack on Tuesday April 29, 2014 @11:36AM
(#7667681)
That 240GB is on 4 sockets, so corresponds roughly to the 85GB/socket cited above, while the Power7 compared was about half the Intel, so about 50GB/socket, while Power8 is allegedly at 240GB/socket.
Thanks for the clarification. HN took ~30-40 minutes before it would show a reply option for this post, so I went ahead and acknowledged the performance difference in a reply to my original reply (ugh). Anyway, that's great to see such high memory bandwidth per socket, rather than summed over the whole machine.
Re:Google's POWER8 server motherboard
by justincormack on Tuesday April 29, 2014 @01:11PM
(#7668407)
If you click the "link" button you can reply sooner...
But I'll respond anyways. It looks like you have GB and Gb per second confused. One is 8x the other.
admin-magazine: claims 120Gb/s [1]
intel claims: 246Gb/s [2]
Independent claims on intel forums range from 120-175Gb/s [3]
Intel's cut sheet for their own latest generation xeon states it only supports 25GB/s (200Gb/s) memory bandwidth [4]
[1] http://www.admin-magazine.com/HPC/Articles/Finding-Memory-Bo...
[2] http://www.intel.com/content/www/us/en/benchmarks/server/xeo...
[3] https://software.intel.com/en-us/forums/topic/383121
[4] http://ark.intel.com/products/75465/Intel-Xeon-Processor-E3-...