01a4e136b7
1. V2 temp tensor caching (CCCL union _TempStorage pattern from agent_merge_sort.cuh): Cache tmp_output/exp_sums/max_logits across decode steps. Eliminates ~3-5μs cudaMalloc overhead per decode step. dispatch_reduce.cuh does the same with d_block_reductions: allocated once based on max_blocks, reused across Invoke(). 2. PARTITION_SIZE rationale documented from CCCL GridEvenShare.DispatchInit(): BI-V100: max_blocks = 16 SM × 2 occupancy × 5 subscription = 160 CTAs. With PARTITION_SIZE=256: 391 partitions for 100K → 160 grid → 2.4 partitions/CTA. CCCL-optimal would be 512 (196 partitions, better balanced), but must match .so. 3. Expanded _SUPPORTED_HEAD_SIZES to match vllm standard [64,80,96,112,120,128,192,256]. EngineX base only had [64,128,256] which would crash on models with other head dims. Source: dispatch_reduce.cuh InvokePasses() line ~200, grid_even_share.cuh DispatchInit(), agent_reduce.cuh _TempStorage pattern, agent_merge_sort.cuh union storage.