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Fun facts, FFT was discovered back in 1965 based on the urgent necessity of discovering and detecting illegal nuke testing activities, just two years after the Partial Test Ban Treaty (PTBT) was signed in 1963 [1].

The first sentence statement in the article mentioning that United States and other nuclear powers committed to the Comprehensive Nuclear-Test-Ban Treaty in 1965 is wrong since the treaty was only signed in 1996 not in 1965 [2].

[1] The Algorithm That Almost Stopped The Development Of Nuclear Weapons:

https://www.iflscience.com/the-algorithm-that-almost-stopped...

[2] The Comprehensive Nuclear-Test-Ban Treaty:

https://www.ctbto.org/our-mission/the-treaty

> El Capitan, housed at Lawrence Livermore National Laboratory in Livermore, Calif., can perform over 2700 quadrillion operations per second at its peak. The previous record holder, Frontier, could do just over 2000 quadrillion peak operations per second.

> El Capitan uses AMD’s MI300a chip, dubbed an accelerated processing unit, which combines a CPU and GPU in one package. In total, the system boasts 44,544 MI300As, connected together by HPE’s Slingshot interconnects.

Seems like a nice win for AMD.

Noting here that 2700 quadrillion operations per second is less than the estimated sustained throughput of productive bfloat16 compute during the training of the large llama3 models, which IIRC was about 45% of 16,000 quadrillion operations per second, ie 16k H100 in parallel at about 0.45 MFU. The compute power of national labs has fallen far behind industry in recent years.

I remember porting code from 32-bit address spaces to 64-bit ones in the 90s and thinking 2^64 was “Kind of infinite” - but this machine does 2^64 operations in 8 seconds…

Anybody know what "Inertial Confinement Fusion" is in the referenced article?

I fail to understand how these nuclear bomb simulations require so much compute power.

Are they trying to model every single atom?

Is this a case where the physicists in charge get away with programming the most inefficient models possible and then the administration simply replies "oh I guess we'll need a bigger supercomputer"

Some may not want to hear this, but these “fastest supercomputer” list is now meaningless because all the Chinese labs have started obfuscating their progress.

A while ago there were a few labs in China in top 10 and they all attracted sanctions / bad attention. Now no Chinese lab report any data now

So, they built this supercomputer to test new and more deadly nuclear weapons. That makes me so "happy". I am absolutely not worried about two nuclear powers being close to the brink of direct war, even as we speak; nor about the abandonment of the course of nuclear disarmament treaty; nor about the repeated talk of a coming war against certain Asian powers. Everything is great and I'll just fawn over the colorful livery and the petaflops figure.

This is great but I absolutely love that poster of el capitan on the supercomputer racks ! Also TIL there is a list of top500 at https://www.top500.org/lists/top500/2024/11/

Do super computers need proximity to other compute nodes in order to perform this kind of computations?

I wonder what would happen if Apple offered people something like iCloud+ in exchange for using their idle M4 compute at night time for a distributed super computer.

This new upstart to the name may win in search results today, but in a few years the first and true El Cap will reclaim its place. It will outlast all of us.

https://en.wikipedia.org/wiki/El_Capitan

This is a major milestone for Oxide Computer team. Congrats