Programming Guide


Intel oneAPI Collective Communications Library (oneCCL)

Intel® oneAPI Collective Communications Library (oneCCL) is a scalable and high-performance communication library for Deep Learning (DL) and Machine Learning (ML) workloads. It develops the ideas that originated in Intel® Machine Learning Scaling Library and expands the design and API to encompass new features and use cases.
oneCCL features include:
  • Built on top of lower-level communication middleware – MPI and libfabrics
  • Optimized to drive scalability of communication patterns by enabling the productive trade-off of compute for communication performance
  • Enables a set of DL-specific optimizations, such as prioritization, persistent operations, out of order execution, etc.
  • DPC++-aware API to run across various hardware targets, such as CPUs and GPUs
  • Works across various interconnects: Intel® Omni-Path Architecture (Intel® OPA), InfiniBand*, and Ethernet
For the complete list of features, documentation, code samples, and downloads, visit the official Intel oneAPI Collective Communications Library website. If you plan to use oneCCL as part of the oneAPI Base Toolkit, consider that premium support is available as a paid option. For the community-supported open-source version, visit the oneCCL GitHub* page.

Product and Performance Information


Performance varies by use, configuration and other factors. Learn more at