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Implement INT4 packing with group scales and a dequantizing matmul, and test it against FP32 with odd K and a partial group.

Two nibbles per byte and a scale per 128 weights sounds like bookkeeping. The grader checks the sign extension, the nibble order, what happens when K is odd or not a multiple of the group, and whether your error test has a bound or just a vibe.

Updated Oct 2026 · Worked answers on inference mechanisms, with calculations, implementation details, and follow-up questions.

Two nibbles per byte and a scale per 128 weights sounds like bookkeeping. The grader checks the sign extension, the nibble order, what happens when K is odd or not a multiple of the group, and whether your error test has a bound or just a vibe.

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Next in this trackWrite a row-wise softmax kernel in Triton that stays correct when a row is longer than the block size, and test it.Next in this trackImplement a ring all-reduce as a simulation over p ranks, verify it against a direct sum, and count the bytes each rank sends.Next in this trackImplement beam search over a paged KV cache, forking beams by sharing blocks and copying only the tail on write.
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