Re:Cray, AMD to Extend DOE’s Exascale Frontier
by gok on Tuesday May 07, 2019 @09:56AM
(#19849319)
1.5 exaflops, 30 megawatts, around 50 GFLOPs per watt? Impressive if true; that's 3x more efficient than the current top of the Green500.
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Re:Cray, AMD to Extend DOE’s Exascale Frontier
by Symmetry on Tuesday May 07, 2019 @09:59AM
(#19849355)
Moore's law might have stopped with the clock gains when Denard scaling gave out but we've still got energy efficiency gains. Koomey's law[1] is holding strong. I don't know if it'll get us all the way to Landauer's Limit[2] but I hope so.
It's probably not a great comparison to compare the theoretical numbers of Frontier to the achieved numbers of the green 500. The achieved flops is pretty much always considerably lower than the theoretical flops. Titan is a 27 PFLOPS machine that achieves 17.6 PFLOPS, sequoia is a 20 PFLOPS machine that achieves 17, summit is a 200 PFLOPS machine that achieves 143, ...
~ 37 GFLOPS/W is probably a better projection if we assume (out of nowhere) that the theoretical/achieved ratio of Frontier is comparable to Summit (75%). Still very impressive.
Well they don't usually hit their peak power usage either; Summit is rated at 13 MW but used less than 10 during its LINPACK run. But fair point.
Re:Cray, AMD to Extend DOE’s Exascale Frontier
by kincl on Tuesday May 07, 2019 @11:55AM
(#19850662)
GPUs help considerably here, taking a look at previous ORNL machines:
Jaguar | 2.3 PF XT5 (CPU-only) | 7 MW for HPL
Titan | 27 PF XK7 (1:1 CPU to GPU) | 8.2 MW
Summit | 186 PF (2:6 CPU to GPU | 8.8 MW
Overall, substantial changes in computing power and 10%-20% increase in power.