BASP: Communication-Efficient Batch-Aware Sequence Parallelism for LLM Training
On the map: LLM reasoning → Test-time compute and efficient thinking
Abstract (arXiv)
Long-context reasoning for large language models (LLMs) is becoming increasingly important, but training over long sequences remains challenging due to massive memory and communication requirements. Sequence parallelism has emerged as an essential technique for addressing bottlenecks in long sequence LLM training. However, we observe that existing sequence parallelism methods are batch-agnostic and apply uniform sequence partitioning across all batch sizes, resulting in inefficient communication. In this paper, we introduce Batch- Aware Sequence Parallelism (BASP), a sequence parallelism approach that leverages batch structure to reduce communication overhead. BASP exploits batch structure by partitioning GPUs into disjoint sequence-parallel groups according to the micro- batch size. This design reduces the all-to-all communication group size, thereby localizing communication and improving training efficiency. Experimental results on an NVIDIA A100 cluster show that BASP improves end-to-end training time by up to 1.17 - 1.31x in Llama and Qwen models compared to standard sequence parallel baselines, while preserving identical model accuracy and memory usage.
Key facts. No citing papers in the map yet (data through 7 Oct 2026). Placed in Test-time compute and efficient thinking, one of 17 directions in LLM reasoning. Builds on 25 of its 30 references that are in the map. First posted on arXiv 2 Sep 2026.
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13 more
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- 2026NSP: Accelerating Variable-Length LLM Training via Nested Sequence Parallelism ↗
- 2026Efficient Scaling of LLM Training with Flexible Context Parallelism
- 2026Characterizing Parallelism Strategies in LLM Inference: Fundamental Compute-Communication Trade-offs
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- 2026Out of the Memory Barrier: A Highly Memory Efficient Training System for LLMs with Million-Token Contexts
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