Patent ID: 9244868
Filing Date: 2016-01-26
CPC Classification: G06F,H04L

Claim Text:
1. A method for IO processing in a storage system, the storage system including a plurality of servers and a shared storage resource, the method comprising: designating one of the plurality of servers as a owner server and the rest of the plurality of servers as peer servers, the owner server serving as a single point of overall lock control for the shared storage resource; determining whether a particular window has become a hot window for a particular peer server at least partially based on a frequency of IO requests directed toward the particular window; sending a lock lease request for the particular window to the owner server when the particular window has become a hot window; retaining the lock lease for the particular window once the lock lease is acquired by the particular peer server; processing IO requests from the particular peer server directed towards the particular window using only local locks of the particular peer server when the lock lease is retained; and conditionally releasing the lease for the particular window, and upon release of the lease for the particular window, the particular peer server is prohibited from sending another lock lease request for the particular window to the owner server unless the particular window transitions to a cold window determined at least partially based on a frequency of IO requests directed toward the particular window and again transitions to a hot window determined at least partially based on the frequency of IO requests directed toward the particular window.