Method for empirically determining a qualified bandwidth of file storage for a shared filed system using a guaranteed rate I/O (GRIO) or non-GRIO process

摘要

A method for preventing oversubscription to a file storage by multiple processes, whether such processes are operating on one node with directly attached storage or on several nodes of a computing cluster sharing a storage area network. Processes or nodes issue requests for bandwidth reservations to a controller daemon. The controller daemon maintains records of all existing bandwidth reservations and ensures that new reservations are granted only if a qualified bandwidth of the file storage will not be exceeded. The qualified bandwidth is empirically determined to take into account installation specific hardware configurations, workloads, and quality of service requirements. In conjunction with suitable enabled client kernels the controller daemon serves to encapsulate all I/O activity including non-reserved I/O activity to the file storage by issuing non-guaranteed bandwidth leases for use by each node in servicing non-guaranteed process I/O activity, such leases being revokable by the controller daemon in order to service new guaranteed bandwidth reservation requests.