The document discusses the Graph500 benchmark for evaluating graph algorithms on parallel systems. The benchmark involves converting an edge list to an internal format, then performing breadth-first searches from random roots. Multiple problem sizes are defined from toy (17GB) to huge (1.1PB). Reference implementations include Octave, OpenMP, Cray XMT, and MPI codes. Untuned performance results on 128-processor Cray XMT show 3.8 trillion traversed edges per second for the toy class. The overall objective is to explore benchmarks for data-intensive, irregular computations on shared-memory platforms.