Zejun Lin | Searcharxiv

arXiv2026

Agent Stack for ML Training Lifecycle: Generation, Validation, and Optimization

Production model development requires repeated architecture design, platform integration, debugging, training, and evaluation. We present an agent stack deployed at LinkedIn with two independently usable agent loops: AutoTorch for model generation and migration, and AutoResearch for model optimization. AutoTorch generates PyTorch models and training pipelines for TensorFlow migration, XGBoost replacement, and new-model development. Executable validation hooks check platform API compliance, trainability, and conversion fidelity on sampled data, guiding iterative repair before engineer review and full-scale distributed training. AutoResearch explores architecture and training-configuration changes through expert-steered or autonomous experimentation. An external orchestrator manages parallel trials, experiment history, candidate selection, and wall-clock budgets across agent sessions. A shared runtime preserves execution state independently of agent reasoning and allocates GPUs separately from agent execution. Across ranking, content understanding, and recommendation workloads, AutoTorch completed generation and full-scale training in 92 of 115 workflow runs (80%). Of these, 77 (83.7%) produced models meeting post-training quality requirements. In a separate cohort, AutoResearch improved the primary task metric on held-out data for 28 of 100 production pipelines. Engineering teams estimate that the stack reduced elapsed end-to-end migration time from approximately eight weeks to two weeks, a 4x speedup.

cs.SE↗

arXiv2020

Deeper Insights into Weight Sharing in Neural Architecture Search

With the success of deep neural networks, Neural Architecture Search (NAS) as a way of automatic model design has attracted wide attention. As training every child model from scratch is very time-consuming, recent works leverage weight-sharing to speed up the model evaluation procedure. These approaches greatly reduce computation by maintaining a single copy of weights on the super-net and share the weights among every child model. However, weight-sharing has no theoretical guarantee and its impact has not been well studied before. In this paper, we conduct comprehensive experiments to reveal the impact of weight-sharing: (1) The best-performing models from different runs or even from consecutive epochs within the same run have significant variance; (2) Even with high variance, we can extract valuable information from training the super-net with shared weights; (3) The interference between child models is a main factor that induces high variance; (4) Properly reducing the degree of weight sharing could effectively reduce variance and improve performance.

cs.LG↗