TECHNIQUES FOR IMPROVING PARALLEL SCAN OPERATIONS

Various technologies and techniques are disclosed for improving performance of parallel scans. Disk head randomization that occurs when performing a parallel scan is minimized by assigning a worker entity to each disk involved in the parallel scan, and by ensuring data is only accessed on a respective disk by the worker entity assigned to the disk. A parallel scan can be performed that is NUMA aware by ensuring a particular sub-set of data is resident in the same memory node during each parallel scan, and by ensuring the particular sub-set of data is processed by a worker entity assigned to a node in which the sub-set of data is resident. A process for performing a parallel scan involves breaking up work into sub-sets, assigning work to each worker entity that corresponds to a respective disk, and having the worker entities process the assigned work to complete the parallel scan.