Patent ID: 9612768
Date: 2017-04-04
CPC Classifications: G06F

Claim:
1. A machine implemented method, comprising: storing data at a first storage tier by a processor executable storage operating system; tracking the data stored at the first storage tier for determining when to move the data to a second storage tier based on a score for rating storage space at the first storage tier determined by a plurality of parameters defined by a policy for the data; transferring the data from the first storage tier to the second storage tier based on the score; and updating a data structure for mapping a virtual identifier of a source storage chunk identified by a source chunk identifier at the first storage tier to a destination chunk identifier of a destination storage chunk at the second storage tier; wherein the source chunk identifier is based on a physical volume block number (PVBN) of a PVBN address space having a plurality of storage chunks with a plurality of contiguous blocks for storing information and the PVBN for the source storage chunk is defined by the source chunk identifier and an offset value for the source storage chunk within the PVBN address space; wherein the virtual identifier and a generation count for the source storage chunk is initially assigned when the data is first written to the source storage chunk and initially maps to the source chunk identifier; wherein the virtual identifier, the generation count and the offset define a transfer volume block number (TVBN) of a TVBN address space, where the TVBN is used to obtain a PVBN for the destination storage chunk to read the data from the destination storage chunk; and wherein instead of PVBN information for the data, TVBN for the data is stored at an indirect block of a tree structure maintained by the storage operating system.