GraphChallenge seeks input from diverse communities to develop graph challenges that take the best of what has been learned from groundbreaking efforts such as GraphAnalysis, Graph500, FireHose, MiniTri, and GraphBLAS to create a new set of challenges to move the community forward.  To scope the effort, the initial GraphChallenges are

Pre-Challenge: PageRank Pipeline This challenge is meant to test some of the specification and reference code approaches that might be used in subsequent challenges.  The community is encouraged to examine this specification and code and provide feedback as to how it can be improved for subsequent challenges.

Static Graph Challenge: Subgraph Isomorphism This challenge seeks to identify a given sub-graph in a larger graph.

Streaming Graph Challenge: Stochastic Block Partition This challenge seeks to identify optimal blocks (or clusters) in a larger graph.

Note on static versus streaming graph challenges.  In static processing, given a large graph G the goal is to evaluate a function f(G).  In stateless streaming, given an additional smaller graph g, the goal is to evaluate the function f(g).  In stateful streaming, the goal is to evaluate a function f(G + g).  Stateful streaming is the focus of the streaming graph challenge.