DynaTrain: Fast Online Parallelism Switching for Elastic LLM Training

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Wang, Yuanqing, Zhang, Yuchen, Lin, Hao, Hu, Junhao, Zhu, Chunyang, Zhang, Quanlu, Li, Boxun, Dai, Guohao, Yang, Zhi, Cheng, Daning, Zhang, Yunquan, Wang, Yu
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866910234375618560
author Wang, Yuanqing
Zhang, Yuchen
Lin, Hao
Hu, Junhao
Zhu, Chunyang
Zhang, Quanlu
Li, Boxun
Dai, Guohao
Yang, Zhi
Cheng, Daning
Zhang, Yunquan
Wang, Yu
author_facet Wang, Yuanqing
Zhang, Yuchen
Lin, Hao
Hu, Junhao
Zhu, Chunyang
Zhang, Quanlu
Li, Boxun
Dai, Guohao
Yang, Zhi
Cheng, Daning
Zhang, Yunquan
Wang, Yu
contents Modern large language model (LLM) training is inherently dynamic: resource fluctuations, RLHF phase shifts, and cluster elasticity continually reshape the optimal parallelism layout, posing a significant challenge to existing training frameworks built around a static execution model. We present DynaTrain, a distributed training system for sub-second, online reconfiguration across arbitrary multi-dimensional parallelism. At its core, we propose a Virtual Parameter Space (VPS) abstraction that unifies all distributed training states under one logical coordinate space, turning any parallelism configuration into a deterministic mapping and collapsing complex transition into manageable geometric intersections. On top of VPS, a state routing-and-transition layer executes rank-local transfers under a memory-aware, deadlock-free schedule, and an Elastic Device Manager overlaps new-world construction with ongoing training to mask topology-change cost. On dense and MoE models up to 235B parameters, DynaTrain reconfigures a 70B dense model in under 2s and a 235B MoE model in 4.36s, outperforming state-of-the-art checkpoint-based and elastic systems by up to three orders of magnitude while preserving correctness.
format Preprint
id arxiv_https___arxiv_org_abs_2605_18815
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle DynaTrain: Fast Online Parallelism Switching for Elastic LLM Training
Wang, Yuanqing
Zhang, Yuchen
Lin, Hao
Hu, Junhao
Zhu, Chunyang
Zhang, Quanlu
Li, Boxun
Dai, Guohao
Yang, Zhi
Cheng, Daning
Zhang, Yunquan
Wang, Yu
Machine Learning
Distributed, Parallel, and Cluster Computing
Modern large language model (LLM) training is inherently dynamic: resource fluctuations, RLHF phase shifts, and cluster elasticity continually reshape the optimal parallelism layout, posing a significant challenge to existing training frameworks built around a static execution model. We present DynaTrain, a distributed training system for sub-second, online reconfiguration across arbitrary multi-dimensional parallelism. At its core, we propose a Virtual Parameter Space (VPS) abstraction that unifies all distributed training states under one logical coordinate space, turning any parallelism configuration into a deterministic mapping and collapsing complex transition into manageable geometric intersections. On top of VPS, a state routing-and-transition layer executes rank-local transfers under a memory-aware, deadlock-free schedule, and an Elastic Device Manager overlaps new-world construction with ongoing training to mask topology-change cost. On dense and MoE models up to 235B parameters, DynaTrain reconfigures a 70B dense model in under 2s and a 235B MoE model in 4.36s, outperforming state-of-the-art checkpoint-based and elastic systems by up to three orders of magnitude while preserving correctness.
title DynaTrain: Fast Online Parallelism Switching for Elastic LLM Training
topic Machine Learning
Distributed, Parallel, and Cluster Computing
url https://arxiv.org/abs/2605.18815