What are the current trends and innovations in parallel communication patterns?

1 Collective communication

Collective communication is a type of communication pattern involving all processors or machines in a parallel system, with a common collective communication operation being a broadcast, where one processor or machine sends the same data to all the others. While collective communication can be useful for synchronizing data, distributing workloads, or aggregating results, it can also be costly and inefficient for large-scale parallel systems. To address this issue, current innovations in collective communication include developing new algorithms and protocols to reduce latency, bandwidth, and memory consumption; leveraging hardware features and accelerators like network switches, GPUs, or FPGAs to support collective communication; and adapting collective communication to different parallel architectures and topologies such as clusters, grids, clouds, or edge devices with different network characteristics and constraints.

2 Point-to-point communication

Point-to-point communication is a type of communication pattern that involves only two processors or machines in a parallel system. For example, one processor or machine can send data to another processor or machine. This type of communication can be useful for exchanging data, coordinating tasks, or implementing load balancing. However, it can also be prone to errors, conflicts, or deadlocks, especially in dynamic and heterogeneous parallel systems. To address these issues, current trends in point-to-point communication include developing new models and abstractions such as MPI or PGAS to simplify and automate the management of point-to-point communication. Additionally, techniques and tools such as error detection and correction, encryption and authentication, or checkpointing and recovery can be employed to enhance the reliability, security, and fault tolerance of point-to-point communication. Finally, new paradigms and frameworks such as the actor model, publish-subscribe, or peer-to-peer can enable more flexible and expressive point-to-point communication.

3 Hybrid communication

Hybrid communication is a type of communication pattern that combines collective and point-to-point communication in a parallel system. It can be used to optimize data movement, balance communication and computation, or solve complex problems. However, hybrid communication can also be challenging and complex, particularly for heterogeneous and adaptive parallel systems. To address this, some current innovations in hybrid communication include developing strategies and heuristics to determine the optimal mix of collective and point-to-point communication for different applications, leveraging technologies and standards that support hybrid communication efficiently and interoperably, and adapting hybrid communication to new domains such as machine learning, big data, or scientific computing.

4 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?