Single Batch Overlap (SBO): Overlaping of Down GEMM with Combine Send - #483
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Co-authored-by: Sulfur6 <huangchun50@gmail.com> Co-authored-by: AniZpZ <aniz1905@gmail.com>
wangfakang
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Nov 6, 2025
Co-authored-by: sky <fakangwang@gmail.com>
Co-authored-by: sky <fakangwang@gmail.com>
qhsc
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Nov 18, 2025
| for (int token_idx = offset + sub_warp_id; token_idx < offset + num_tokens_to_send; token_idx += num_warps_per_group) { | ||
| if (overlap or (not is_rank_masked<true>(mask_buffer_ptr, dst_rank))) { | ||
| auto token_start_idx = overlap ? local_expert_signal_idx * block_m : offset; | ||
| auto token_end_idx = overlap ? min((local_expert_signal_idx + 1) * block_m, num_tokens_per_expert) : (offset + num_tokens_to_send); |
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Hi~ I have tried this great feature, and foud that combine_send was slower than the non-overlap situation, maybe block_m is too big for one SM in each itertions? I
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You may consider increasing num_sms from the default value of 3 to 4-6. When block_m is set to 64, given that num_warps is 32: if num_token <= 32, one SM sends a single round; if 32 < num_token <= 64, one SM needs to send two rounds. Two rounds may take slightly longer than the origin combined send, but you can increase parallelism by raising num_sms.
jiafuzha
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Jul 23, 2026
…deepseek-ai#483) * feat: Overlap down gemm and combine send Co-authored-by: Sulfur6 <huangchun50@gmail.com> Co-authored-by: AniZpZ <aniz1905@gmail.com> * Add validation to new parameters Co-authored-by: sky <fakangwang@gmail.com> * Optimize judgment logic Co-authored-by: sky <fakangwang@gmail.com> * add comments to explain the changes in NUM_WORKSPACE_BYTES * shared_vaild_signal_prefix_sum added to the end of smem_buffer * shared_vaild_signal_prefix_sum added to the end of smem_buffer * fix format * bugfix --------- Co-authored-by: Sulfur6 <huangchun50@gmail.com> Co-authored-by: AniZpZ <aniz1905@gmail.com> Co-authored-by: sky <fakangwang@gmail.com>
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The DeepEP implementation for SBO (DeepEP #390) will be merged into the antgroup-opt branch.