Patent ID: 8326893

Claim:
A computer implemented method executed in a computer system to manage the storage of data in a storage system, comprising: allocating a container data set in the storage system; including an entry in a file allocation catalog for the allocated container data set indicating an address range of data allocated to the container data set, wherein the file allocation catalog maps data sets to address ranges in the storage system; generating a virtual file allocation catalog for the container data set, wherein the virtual file allocation catalog includes entries for data sets allocated in the address range of the container data set; receiving a request to allocate a data set; determining whether the data set to allocate has a size less than a threshold size; including an entry in the virtual file allocation catalog to allocate the data set in the address range of the container data set in response to determining that the data set to allocate size is less than the threshold size; and including an entry in the file allocation catalog to allocate the data set in response to determining that the data set to allocate size is greater than the threshold size.