OmniSage: Large Scale, Multi-Entity Heterogeneous Graph Representation Learning
It addresses the problem of fragmented representation learning techniques for improving search and recommender systems at Pinterest, offering a practical solution with measurable impact.
The paper tackles the challenge of unifying diverse representation learning methods for web applications by introducing OmniSage, a large-scale framework that integrates graph neural networks, content-based models, and user sequence models, resulting in an approximate 2.5% increase in sitewide repins across five applications at Pinterest.
Representation learning, a task of learning latent vectors to represent entities, is a key task in improving search and recommender systems in web applications. Various representation learning methods have been developed, including graph-based approaches for relationships among entities, sequence-based methods for capturing the temporal evolution of user activities, and content-based models for leveraging text and visual content. However, the development of a unifying framework that integrates these diverse techniques to support multiple applications remains a significant challenge. This paper presents OmniSage, a large-scale representation framework that learns universal representations for a variety of applications at Pinterest. OmniSage integrates graph neural networks with content-based models and user sequence models by employing multiple contrastive learning tasks to effectively process graph data, user sequence data, and content signals. To support the training and inference of OmniSage, we developed an efficient infrastructure capable of supporting Pinterest graphs with billions of nodes. The universal representations generated by OmniSage have significantly enhanced user experiences on Pinterest, leading to an approximate 2.5% increase in sitewide repins (saves) across five applications. This paper highlights the impact of unifying representation learning methods, and we make the model code publicly available at https://github.com/pinterest/atg-research/tree/main/omnisage.