Patent ID: 8705538

Claim:
A method comprising: selecting a path by which to send an I/O request from a host to an associated storage subsystem from among a plurality of paths from the host to the associated storage subsystem, the selecting comprising: identifying, for each of the plurality of paths, a first limitation on a traffic level for I/O requests having a first urgency level, wherein the first urgency level does not comprise the highest urgency level; tracking a first metric corresponding to the first limitation for each of the plurality of paths; identifying a first set of paths whose first metric does not exceed its first limitation; and transmitting a first I/O request having the first urgency level by one of the first set of identified paths; identifying, for each of the plurality of paths, a second limitation on the traffic level for I/O requests having a second urgency level, wherein the second urgency level does not comprise the highest urgency level; tracking a second metric corresponding to the second limitation for each of the plurality of paths; identifying a second set of paths whose second metric does not exceed its second limitation; and transmitting a second I/O request having the second urgency level by one of the second set of identified paths.