Collective Communication
Provides standard interfaces to common global operations
- Synchronization
- Communications, i.e. movement of data
- Collective computation
A collective operation uses a process group
- All processes in group call same operation at (roughly) the same time
- Groups are constructed “by hand” with MPI group manipulation routines or by using MPI topology-definition routines
Message tags not needed (generated internally)
All collective operations are blocking.