Patent attributes
A technique for managing storage space includes establishing an MSR (minimum space reservation) of a thin file system built upon a storage pool. In response to a set of storage requests to the file system to store new data, the method further includes obtaining an additional space guarantee from the storage pool. After deleting data from the file system such that the size of the file system falls below the MSR, the technique further includes performing a space reclaim operation, the space reclaim operation (i) compacting the file system to a size less than the MSR, (ii) canceling the additional space guarantee such that the storage pool no longer guarantees the additional space for the file system, and (iii) continuing to reserve the full MSR of the file system, even though the size of the file system is smaller than the MSR.
