🤖 AI Summary
To address low resource utilization in distributed training on heterogeneous GPU clusters, this paper proposes an automated parallel training framework. Methodologically, it introduces: (1) a fine-grained cross-operator parallelism planner that enables hardware-aware, customized operator partitioning for heterogeneous devices; (2) a heterogeneity-aware 1F1B (one-forward-one-backward) scheduling mechanism that dynamically reorders micro-batch execution to maximize compute-communication overlap; and (3) an integrated optimization combining load balancing, communication cost modeling, and cross-cluster memory/bandwidth adaptation. Experimental evaluation on real-world heterogeneous GPU clusters demonstrates that the framework achieves 1.3–1.6× speedup over state-of-the-art systems—including PyTorch DDP and DeepSpeed—while significantly alleviating communication bottlenecks and improving end-to-end training throughput and hardware resource utilization.
📝 Abstract
With the rapid evolution of GPU architectures, the heterogeneity of model training infrastructures is steadily increasing. In such environments, effectively utilizing all available heterogeneous accelerators becomes critical for distributed model training. However, existing frameworks, which are primarily designed for homogeneous clusters, often exhibit significant resource underutilization when deployed on heterogeneous accelerators and networks. In this paper, we present Hapt, an automated parallel training framework designed specifically for heterogeneous clusters. Hapt introduces a fine-grained planner that efficiently searches a wide space for the inter-operator parallel strategy, enabling Hapt to alleviate communication overheads while maintaining balanced loads across heterogeneous accelerators. In addition, Hapt implements a heterogeneity-aware 1F1B scheduler that adaptively adjusts the execution timing and ordering of microbatches based on network characteristics, maximizing computation-communication overlap under cross-cluster interconnects while incurring only minimal memory overhead. Our evaluation results show that Hapt can deliver 1.3x-1.6x higher performance on heterogeneous clusters than state-of-the-art training frameworks.