Patent ID: 8868610

Claim:
A method for accessing data in a clustered file system residing in a data storage unit that is shared by a plurality of host computers, each of which includes a processor and a memory coupled with the processor, wherein the method is carried out in a host computer that is one of the plurality of host computers and comprises: receiving, from a virtual machine process executing within the host computer, an open request for a virtual disk file in the clustered file system, the virtual disk file having a lock associated therewith; determining whether the virtual disk file is locked by another one of the plurality of host computers; in the event the file is not locked by one of the plurality of host computers, determining whether the open request meets one or more qualifications for allowing a limited lease; and in the event the open request meets the qualifications for a limited lease, establishing a limited lease of the virtual disk file for the host computer, without acquiring the lock for the file, the limited lease giving the virtual machine process read-only access to the virtual machine file while the lease is in effect.