Real-time storage area network

摘要

A cluster of computing systems is provided with guaranteed real-time access to data storage in a storage area network. Processes issue request for bandwidth reservation which are initially handled by a daemon on the same node as the requesting processes. The local daemon determines whether bandwidth is available and, if so, reserves the bandwidth in common hardware on the local node, then forwards requests for shared resources to a master daemon for the cluster. The master daemon makes similar determinations and reservations for resources shared by the cluster, including data storage elements in the storage area network and grants admission to the requests that don't exceed total available bandwidth.

主权项

1. A method for accessing a storage area network (SAN) by real-time applications, the method comprising:
receiving at a master node of a plurality of nodes, from a real-time application executing on the master node, a first request for reservation of a first specified amount of bandwidth to access components in the SAN to a shared resource of the SAN; identifying that that one or more components in the SAN has sufficient bandwidth capacity to service the first request; generating, at the master node of the plurality of nodes, a second request for reservation of a second specified amount of bandwidth to access the components in the storage area network to the shared resource of the SAN, wherein the second request requests bandwidth to be granted to a process executing at a second node of the plurality of nodes, and the second node is a client node of the master node; allocating a percentage of the total bandwidth of the shared resource to each of a plurality of nodes according to the first and the second request, wherein each individual node of the plurality of nodes maintains allocation information about the shared resource, and the allocation information maintained on an individual node includes the amount of bandwidth of the shared resource that has been allocated to the individual node; and allowing access to the SAN by the real-time application, wherein data accessed by the real-time application is communicated over a network communication interface, and a local daemon executing at the second node allocates an additional amount of bandwidth to access the SAN to an application executing on at least one node of the plurality of nodes without sending a request to the master node.