feat(peft): expand_shared_outer export flag for shared-outer MoE LoRA - #5588
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feat(peft): expand_shared_outer export flag for shared-outer MoE LoRA#5588HollowMan6 wants to merge 1 commit into
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Shared-outer MoE LoRA exports the shared adapter side as a single `[1, ...]` tensor under an expert-agnostic name (SGLang contract). vLLM's 2D `pack_moe` path for text MoE models expects per-expert 2D tensors, so it can't find the shared factor and crashes at `lora.optimize()` (`lora_b is None`). So this PR adds `expand_shared_outer` to the adapter export path. When set, the shared 2D factor is replicated under per-expert 2D names (reused, not cloned); training keeps the shared parameter. Default `False` preserves the existing layout. Signed-off-by: Hollow Man <hollowman@opensuse.org>
yaoyu-33
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Aug 14, 2026
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What does this PR do ?
Related to #3958
Shared-outer MoE LoRA exports the shared adapter side as a single
[1, ...]tensor under an expert-agnostic name (SGLang contract). vLLM's 2Dpack_moepath for text MoE models expects per-expert 2D tensors, so it can't find the shared factor and crashes atlora.optimize()(lora_b is None). So this PR addsexpand_shared_outerto the adapter export path. When set, the shared 2D factor is replicated under per-expert 2D names (reused, not cloned); training keeps the shared parameter. DefaultFalsepreserves the existing layout.Changelog
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