Book Image

Apache Spark Graph Processing

Book Image

Apache Spark Graph Processing

Overview of this book

Table of Contents (16 chapters)
Apache Spark Graph Processing
Credits
Foreword
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Summary


AggregateMessages provides a functional abstraction for aggregating neighborhood information in Spark graphs. This operator applies a user-defined sendMsg function to each edge in the graph using EdgeContext. Each EdgeContext class accesses the required information about the edge and passes that information to its source node and/or destination node using the sendToSrc and/or sendToDst methods respectively. After all messages have been received by the nodes, the mergeMsg function is used to aggregate those messages at each node.

In the next chapter, we will introduce another operator called Pregel, which will be useful for creating custom iterative graph-processing algorithms.