1. A computer implemented method comprising: identifying, by a computer, a first set of nodes in a networked computer system, the first set of nodes included in a first hash computation that clusters the first set of nodes into communities, wherein each node of the first set of nodes is associated with a user on a social networking system, and the first hash computation clusters the first set of nodes into communities based on connections between the users on the social networking system; generating, by the computer, an application shard space including a first space and a second space; mapping, by the computer, the first set of nodes to application shards in the first space based on the first hash computation, the application shards in the first space assigned to a first set of machines of the networked computer system; and maintaining, by the computer, the second space for mappings of nodes not included in the first hash computation to application shards in the second space, wherein the second space is reserved for nodes that have not been included in any hash computation.