BG uses the Zipfian distribution to generate its workload of requests. This distribution enables BG to emulate scenarios such as 20% of members generating 80% of requests. The exponent of the distribution controls the degree of skewness.
BGCoord partitions members of the social network across the N BGClients logically, requiring each BGClient to generate requests for its fragment of members. This enables BG to scale to a large number of BGClients. Decentralized Zipfian (D-Zipfian), is a technique that generates a Zipfian distribution that is independent of the number of BGClients used by BG. Thus, the generated distribution with a given exponent of D-Zipfian is the same with 1 BGClients and 10 BGClients (arbitrary values of N).
We speculate D-Zipfian is useful for other use cases. One may download a standalone version of D-Zipfain, independent of BG, from USC's database lab web site.