Patent ID: 7533235

Claim:
A method comprising: maintaining a flexible volume within an aggregate of storage; stacking a reserved portion of the flexible volume with a reserved portion of the aggregate, wherein at least some of the reserved portion of the aggregate acts as the reserved portion of the flexible volume; creating the flexible volume to have a size; guaranteeing a portion of the flexible volume to have a size less than the size of the flexible volume, the guaranteeing comprising: determining an amount of available space in the aggregate; determining a type of guarantee for the flexible volume; determining the size of the guaranteed portion of the flexible volume based on the type of guarantee and the size of an unreserved portion of the flexible volume; and if the size of the guaranteed portion of the flexible volume is greater than the available space in the aggregate, returning an error message; receiving a request to write metadata for the flexible volume; and in response to the request, writing the metadata to the reserved portion of the aggregate.