Intel® oneAPI Collective Communications Library (oneCCL) Developer Guide and Reference
                    
                        ID
                        772609
                    
                
                
                    Date
                    6/30/2025
                
                
                    Public
                
            Introduction
oneAPI Collective Communications Library (oneCCL) (oneCCL) provides an efficient implementation of communication patterns used in deep learning.
oneCCL features include:
- Built on top of lower-level communication middleware – Intel® MPI Library and libfabrics. 
- Optimized to drive scalability of communication patterns. It supports collectives and point-to-point (send/receive) primitives. 
- Works across various interconnects: InfiniBand*, Cornelis Networks*, and Ethernet. 
- Provides common API sufficient to support communication workflows within Deep Learning / distributed frameworks (such as PyTorch*, Horovod*). 
oneCCL package comprises the oneCCL Software Development Kit (SDK) and the Intel® MPI Library Runtime components.