1. A computer system, the system comprising: a processor executing an operating system embodied in non-transitory computer-readable media; a memory; and at least one data storage device, the operating system comprising: an operating system kernel; at least one filesystem controlling access to the at least one data storage device; and a toolkit module installed within the operating system kernel; wherein the toolkit module monitors input/output (I/O) calls communicated via a datapath between at least one software application being executed on the processor and the filesystem; and wherein the toolkit module inserts one or more tools into the datapath, the one or more tools each executing a predefined function based on observation of a first set of the I/O calls being communicated in the datapath; wherein the one or more tools comprises a statistics tool, wherein the statistics tool generates statistical information from each I/O call within the first set of the I/O calls made to specified files and directories; wherein the statistical information includes at least one of: a number of I/O calls made to the specified files and directories; and a statistic measuring how much data is being transferred between the at least one software application and the specified files and directories.