Data can be processed in parallel across a cluster of nodes using a parallel processing framework. Using Web services calls between components allows the number of nodes to be scaled as necessary, and allows developers to build applications on the framework using a Web services interface. A job scheduler works together with a queuing service to distribute jobs to nodes as the nodes have capacity, such that jobs can be performed in parallel as quickly as the nodes are able to process the jobs. Data can be loaded efficiently across the cluster, and levels of nodes can be determined dynamically to process queries and other requests on the system.