Intel® oneAPI Collective Communications Library Developer Guide and Reference
ID
772609
Date
3/31/2023
Public
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Fusion of Communication Operations
In some cases, it may be beneficial to postpone execution of communication operations and execute them all together as a single operation in a batch mode. This can reduce operation setup overhead and improve interconnect saturation.
oneCCL provides several knobs to enable and control such optimization:
The fusion is enabled by CCL_FUSION.
The advanced configuration is controlled by:
NOTE:
For now, this functionality is supported for allreduce operations only.