Patent application number | Description | Published |
20120179891 | EXTENSION OF WRITE ANYWHERE FILE SYSTEM LAYOUT - A file system layout apportions an underlying physical volume into one or more virtual volumes (vvols) of a storage system. The underlying physical volume is an aggregate comprising one or more groups of disks, such as RAID groups, of the storage system. The aggregate has its own physical volume block number (pvbn) space and maintains metadata, such as block allocation structures, within that pvbn space. Each vvol has its own virtual volume block number (vvbn) space and maintains metadata, such as block allocation structures, within that vvbn space. Notably, the block allocation structures of a vvol are sized to the vvol, and not to the underlying aggregate, to thereby allow operations that manage data served by the storage system (e.g., snapshot operations) to efficiently work over the vvols. | 07-12-2012 |
20130262805 | Method and Apparatus for Identifying and Eliminating Duplicate Data Blocks and Sharing Data Blocks in a Storage System - A method for sharing data blocks in a hierarchical file system in a storage server includes allocating a plurality of data blocks in the file system, and sharing data blocks in the file system, without using a persistent point-in-time image, to avoid duplication of data blocks. A method for identifying data blocks that can be shared includes computing a fingerprint for each of multiple data blocks to be written to a storage facility and storing the fingerprint with information identifying the data block in an entry in a set of metadata. The set of metadata is used to identify data blocks which are duplicates. | 10-03-2013 |
20140082281 | EXTENSION OF WRITE ANYWHERE FILE SYSTEM LAYOUT - A file system layout apportions an underlying physical volume into one or more virtual volumes (vvols) of a storage system. The underlying physical volume is an aggregate comprising one or more groups of disks, such as RAID groups, of the storage system. The aggregate has its own physical volume block number (pvbn) space and maintains metadata, such as block allocation structures, within that pvbn space. Each vvol has its own virtual volume block number (vvbn) space and maintains metadata, such as block allocation structures, within that vvbn space. Notably, the block allocation structures of a vvol are sized to the vvol, and not to the underlying aggregate, to thereby allow operations that manage data served by the storage system (e.g., snapshot operations) to efficiently work over the vvols. The file system layout extends the file system layout of a conventional write anywhere file layout system implementation, yet maintains performance properties of the conventional implementation. | 03-20-2014 |
20150081966 | DENSE TREE VOLUME METADATA ORGANIZATION - In one embodiment, a node coupled to one or more storage devices executes a storage input/output (I/O) stack having a volume layer. The volume layer manages volume metadata embodied as mappings from offsets of a logical unit (LUN) to extent keys associated with storage locations for extents on the one or more storage devices. Volume metadata is maintained as a dense tree metadata structure representing successive points in time. The dense tree metadata structure has multiple levels, wherein a top level of the dense tree metadata structure represents newer volume metadata changes and descending levels of the dense tree metadata structure represent older volume metadata changes. The node accesses a latest version of changes to the volume metadata by searching from the top level to the descending levels in the dense tree metadata structure. | 03-19-2015 |
20150095346 | EXTENT HASHING TECHNIQUE FOR DISTRIBUTED STORAGE ARCHITECTURE - In one embodiment, a technique is provided for distributing data and associated metadata within a distributed storage architecture. A set of hash tables that embody mappings of cluster-wide identifiers associated with storage locations are stored for write data of write requests organized into extents. A hash value is generated from a hash function applied to each extent. The hash value is overloaded and used for multiple purposes within the distributed storage architecture, including (i) a remainder computation on the hash value to select a bucket of a plurality of buckets representative of the extents, (ii) a hash table selector of the hash value to select a hash table from the set of hash tables, and (iii) a hash table index computed from the hash value to select an entry from a plurality of entries of the selected hash table having a cluster-wide identifier identifying a storage location for the extent. | 04-02-2015 |
20150095347 | EXTENT HASHING TECHNIQUE FOR DISTRIBUTED STORAGE ARCHITECTURE - In one embodiment, an extent hashing technique is used to efficiently distribute data and associated metadata substantially evenly among nodes of a cluster. The data may be write data associated with a write request issued by a host and received at a node of the cluster. The write data may be organized into one or more extents. A hash function may be applied to the extent to generate a result which may be truncated or trimmed to generate a hash value. A hash space of the hash value may be divided into a plurality of buckets representative of the write data, i.e., the extents, and the associated metadata, i.e., extent metadata. A number of buckets may be assigned to each extent store instance of the nodes to distribute ownership of the buckets, along with their extents and extent metadata, across all of the extent store instances of the nodes. | 04-02-2015 |
20150134616 | SNAPSHOTS AND CLONES OF VOLUMES IN A STORAGE SYSTEM - In one embodiment, snapshots and/or clones of storage objects are created and managed by a volume layer of a storage input/output (I/O) stack executing on one or more nodes of a cluster. Illustratively, the snapshots and clones may be represented as independent volumes, and embodied as respective read-only copies (snapshots) and read-write copies (clones) of a parent volume. Volume metadata is illustratively organized as one or more multi-level dense tree metadata structures, wherein each level of the dense tree metadata structure (dense tree) includes volume metadata entries for storing the metadata. Each snapshot/clone may be derived from a dense tree of the parent volume (parent dense tree). Portions of the parent dense tree may be shared with the snapshot/clone. | 05-14-2015 |
20150134879 | SNAPSHOTS AND CLONES OF VOLUMES IN A STORAGE SYSTEM - In one embodiment, a node coupled to one or more storage devices executes a storage input/output (I/O) stack having a volume layer that manages volume metadata. The volume metadata is organized as one or more dense tree metadata structures having a top level residing in memory and lower levels residing on the one or more storage devices. The dense tree metadata structures include a first dense tree metadata structure associated with a parent volume and a second dense tree metadata structure associated with a copy of the parent volume. The top level of the first dense tree metadata structure may be copied to the second dense tree metadata structure. The lower levels of the first dense tree metadata structure are initially shared with the second dense tree metadata structure. The shared lower levels may eventually be split as the parent volume diverges from the copy of the parent volume. | 05-14-2015 |