alt Hacker NewsI wonder how well this works with MoE architectures?
For dense LLMs, like llama-3.1-8B, you profit a lot from having all the weights available close to the actual multiply-accumulate hardware.
With MoE, it is rather like a memory lookup. Instead of a 1:1 pairing of MACs to stored weights, you suddenly are forced to have a large memory block next to a small MAC block. And once this mismatch becomes large enough, there is a huge gain by using a highly optimized memory process for the memory instead of mask ROM.
At that point we are back to a chiplet approach...
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brainless • today at 9:30 AM
If each of the Expert models were etched in Silicon, it would still have massive speed boost, isn't it?
I feel printing ASIC is the main block here.
For comparison I wanted to write on how Google handles MoE archs with its TPUv4 arch.
They use Optical Circuit Switches, operating via MEMS mirrors, to create highly reconfigurable, high-bandwidth 3D torus topologies. The OCS fabric allows 4,096 chips to be connected in a single pod, with the ability to dynamically rewire the cluster to match the communication patterns of specific MoE models.
The 3D torus connects 64-chip cubes with 6 neighbors each. TPUv4 also contains 2 SparseCores which specialize handling high-bandwidth, non-contiguous memory accesses.
Of course this is a DC level system, not something on a chip for your pc, but just want to express the scale here.
*ed: SpareCubes to SparseCubes