NetRay is a graph visiualization and mining tool which runs on top of Hadoop platform. NetRay can be used for drawing the spy plot, distribution plot, and correlation plot of big graphs.



The details of Net-Ray can be found in the following paper [PDF]:

U Kang, Jay-Yoon Lee, Danai Koutra, and Christos Faloutsos.
Net-Ray: Visualizing and Mining Billion-Scale Graphs.
Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD) 2014, Tainan, Taiwan. 
If your work uses or refers to Net-Ray, please cite the papers using the following bibtex entries:
  author    = {U. Kang and
               Jay-Yoon Lee and
               Danai Koutra and
               Christos Faloutsos},
  title     = {Net-Ray: Visualizing and Mining Billion-Scale Graphs},
  booktitle = {PAKDD},
  year      = {2014},


NetRay is avaiable as an open source. Download here.


Here is the visualization based on NetRay.

(a) adjacency matrix of 1.4 billion-node web graph (b) out degree distribution of 1.4 billion-node web graph (c) correlation plots of 1.4 billion-node web graph