Performance of MPI Sends of Non-Contiguous Data
- Resource Type
- Conference
- Authors
- Eijkhout, Victor
- Source
- 2020 IEEE International Parallel and Distributed Processing Symposium Workshops (IPDPSW) Parallel and Distributed Processing Symposium Workshops (IPDPSW), 2020 IEEE International. :889-895 May, 2020
- Subject
- Bioengineering
Communication, Networking and Broadcast Technologies
Components, Circuits, Devices and Systems
Computing and Processing
Bandwidth
Manuals
Finite element analysis
Protocols
Hardware
Arrays
Resource management
- Language
We present an experimental investigation of the performance of MPI derived datatypes. While solutions with hardware support can achieve high performance, we show that vanilla approaches fall short. For messages up to the megabyte range most schemes perform comparably to each other and to manual copying into a regular send buffer. However, for large messages the internal buffering of MPI causes marked differences in efficiency. We show how schemes that acknowledge the importance of buffer management give both the highest performance and a simple usage.