An input/output (I/O) method, system, and computer program product are disclosed. An incoming I/O request is received from an application running on a processor. A tree structure including processor-executable instructions defines one or more layers of processing associated with the I/O request. The instructions divide the data in the I/O request into one or more chunks at each of the one or more layers of processing. Each instruction has an associated data dependency to one or more corresponding instructions in a previous layer. The instructions are sorted into an order of processing by determining a location of each chunk and data dependencies between chunks of different layers of processing. One or more instructions are inserted into a schedule that depends at least partly on the order of processing. The I/O request is serviced by executing the instructions according to the schedule with the processor according to the order of processing.