Move AllGather kernel args to Types.h (P1-D2) #514
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Summary: Implements native AVG support for the PAT (Parallel All-to-All Transpose) algorithm in ReduceScatter. ## Problem Baseline NCCL doesn't support PAT + AVG op. - if `NCCL_ALGO=reducescatter:pat` is NOT SET: NCCL would fallback back to Ring algorithm - if `NCCL_ALGO=reducescatter:pat` is SET: fail with `ncclInvalidUsage - Error : no algorithm/protocol available for function` ## Solution This diff enables native AVG with PAT algorithm for reduce scatter. It divides integer nRanks at last step when writing final sum result into recvbuf. **Documentation Added:** - `meta/collectives/docs/ReduceScatterPat.md` - Comprehensive PAT algorithm documentation including 5-phase breakdown and 8-rank visualization - `meta/collectives/docs/ReduceScatterPatAvg.md` - PAT AVG design details, multi-chunk handling, and implementation notes **Key Implementation:** - Add `isFinalWrite` flag to `ncclPatStep` struct (set in Phase 4) to correctly apply division for all chunks in multi-chunk transfers (fixes large message bug) - Add FuncPatAvg<T> template that uses FuncSum for reduction and applies division as a postOp in final write step - Add ncclDevPatAvg enum for kernel dispatch - Update generate.py and def_build.bzl for PatAvg kernel generation - Enable via NCCL_ALGO=reducescatter:pat_postdiv **Meta overlay pattern used to minimize upstream changes:** - meta/device/FuncPatAvg.cuh: Full implementation (~120 lines) - meta/collectives/PatAvgAlgoHelper.h: Helper functions with lazy env detection - All src/ changes (~15 lines) are marked with `[META:PAT_AVG]` comments for rebasing tracking Differential Revision: D91948601
Summary: Add a Claude Code agent definition for reviewing ctran code changes. The agent: - Reviews diffs for correctness (thread safety, test coverage, code abstraction) - Performs performance review (benchmark requirements, roofline analysis) - References CLAUDE.md as the authoritative source for coding standards - Outputs structured feedback with clear recommendations (APPROVE/NEEDS_CHANGES/NEEDS_HUMAN_REVIEW) This agent should be invoked after code changes are made to provide automated review feedback before human review. Differential Revision: D91963243
Summary: Move CtranKernelSendArgs, CtranKernelRecvArgs, and CtranKernelSendRecvArgs from gpe/CtranGpeDev.h to algos/SendRecv/Types.h as ctran::sendrecv::KernelSendArgs, KernelRecvArgs, and KernelSendRecvArgs respectively. Part of KernelElem cleanup Phase 1. Naming follows the convention: - Remove "Ctran" prefix - Keep "Kernel" prefix - Keep "Send/Recv/SendRecv" suffix since they're distinct types Differential Revision: D91983715
Summary: Move CtranKernelAllGatherArgs from gpe/CtranGpeDev.h to algos/AllGather/Types.h as ctran::allgather::KernelArgs. Part of KernelElem cleanup Phase 1. Naming follows the convention: - Remove "Ctran" prefix - Keep "Kernel" prefix - Omit algorithm name since namespace provides context Differential Revision: D91983718
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Summary:
Move CtranKernelAllGatherArgs from gpe/CtranGpeDev.h to algos/AllGather/Types.h
as ctran::allgather::KernelArgs. Part of KernelElem cleanup Phase 1.
Naming follows the convention:
Differential Revision: D91983718