1. A computing apparatus for analyzing or debugging a data flow program, comprising: one or more computing hardware processors; a spectral graph partitioner to execute on the one or more computing hardware processors to partition a data flow graph associated with the data flow program into a plurality of subgraphs and output results of the partition, wherein the data flow program operates on the one or more computing hardware processors or other one or more computing hardware processors of another computing apparatus; wherein the spectral graph partitioner includes: a vector estimator to generate one or more estimated vectors for a matrix describing the graph through minimization of a function on the vectors to partition the graph into the plurality of subgraphs; and a cluster determiner to: define a multi-dimensional space based on the one or more estimated vectors; and cluster nodes of the graph to form the plurality of subgraphs in the multi-dimensional space; an analyzer or debugger to execute on the one or more computing hardware processors to analyze or debug the data flow program using the plurality of subgraphs in the multi-dimensional space formed from the clustering; and wherein to generate the one or more estimated vectors, the vector estimator generates at least a vector v using a function that depends on at least differences between a plurality of coordinates of the vector v or a difference between a number of nodes in the graph and a magnitude of the vector v.