Distributing the training of large machine learning models across multiple machines is essential for handling massive datasets and complex architectures. One prominent approach involves a centralized parameter server architecture, where a central server stores the model parameters and worker machines perform computations on data subsets, exchanging updates with the server. This architecture facilitates parallel processing and reduces the training time significantly. For instance, imagine training a model on a dataset too large to fit on a single machine. The dataset is partitioned, and each worker trains on a portion, sending parameter updates to the central server, which aggregates them and updates the global model.
This distributed training paradigm enables handling of otherwise intractable problems, leading to more accurate and robust models. It has become increasingly critical with the growth of big data and the increasing complexity of deep learning models. Historically, single-machine training posed limitations on both data size and model complexity. Distributed approaches, such as the parameter server, emerged to overcome these bottlenecks, paving the way for advancements in areas like image recognition, natural language processing, and recommender systems.