fix: Disable double DDP construction inside build_model() via runtime patch #264
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wenxie-amd
approved these changes
Nov 3, 2025
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Recent Megatron changes wrap DDP twice — once on the default stream, and once inside a torch.cuda.Stream() block — which can cause deadlocks or hangs under ROCm multi-GPU training.
This branch introduces a runtime monkey-patch in Primus to neutralize the second DDP construction without modifying Megatron source files.