Patent ID: 7899989
Filing Date: 2011-03-01
Classification: G06F

Abstract:
1. A method for writing logical blocks into a storage pool organized in a hierarchical tree structure, comprising: receiving a request to write first logical block; selecting a block allocation policy, by a file system associated with the storage pool, from a plurality of allocation policies; obtaining a list of free physical blocks in the storage pool; allocating a first physical block from the list of free physical blocks, based on the block allocation policy; writing the first logical block to the first physical block on a first level of the hierarchical tree structure; calculating a first checksum for the first logical block; assembling a second logical block, wherein the second logical block comprises a first block pointer that stores the first checksum and references the first logical block; allocating a second physical block from the list of free physical blocks, based on the block allocation policy; writing the second logical block to the second physical block on a second level of the hierarchical tree structure; calculating a second checksum for the second logical block; assembling a third logical block, wherein the third logical block comprises a second block pointer that stores the second checksum and references the second logical block; allocating a third physical block from the list of free physical blocks, based on the block allocation policy; and writing the third logical block to the third physical block on a third level of the hierarchical tree structure.