A 121 billion edge graph is too large to fit within the confines of a single machine. Fortunately, Titan/Cassandra is a distributed graph database able to repre

A 121 billion edge graph is too large to fit within the confines of a single machine. Fortunately, Titan/Cassandra is a distributed graph database able to represent a graph across a multi-machine cluster. The Amazon EC2 cluster utilized for the simulation was composed of 16 hi1.4xlarge machines...The 10 terabyte, 121 billion edge graph was loaded into the cluster in 1.48 days at a rate of approximately 1.2 million edges a second with 0 failed transactions. How many machines can you add so that Titan continues to scale linearly? And have you run the benchmarks on Google Compute Engine to compare?