摘要:
A technique is disclosed for restoring data of sparse volumes, where one or more block pointers within the file system structure are marked as ABSENT, and fetching the appropriate data from an alternate location on demand. Client data access requests to the local storage system initiate a restoration of the data from a backing store as required. A demand generator can also be used to restore the data as a background process by walking through the sparse volume and restoring the data of absent blocks. A pump module is also disclosed to regulate the access of the demand generator. Once all the data has been restored, the volume contains all data locally, and is no longer a sparse volume.
摘要:
A technique is disclosed for restoring data of sparse volumes, where one or more block pointers within the file system structure are marked as ABSENT, and fetching the appropriate data from an alternate location on demand. Client data access requests to the local storage system initiate a restoration of the data from a backing store as required. A demand generator can also be used to restore the data as a background process by walking through the sparse volume and restoring the data of absent blocks. A pump module is also disclosed to regulate the access of the demand generator. Once all the data has been restored, the volume contains all data locally, and is no longer a sparse volume.
摘要:
A network caching system has a multi-protocol caching filer coupled to an origin server to provide storage virtualization of data served by the filer in response to data access requests issued by multi-protocol clients over a computer network. The multi-protocol caching filer includes a file system configured to manage a sparse volume that “virtualizes” a storage space of the data to thereby provide a cache function that enables access to data by the multi-protocol clients. To that end, the caching filer further includes a multi-protocol engine configured to translate the multi-protocol client data access requests into generic file system primitive operations executable by both the caching filer and the origin server.
摘要:
A network caching system has a multi-protocol caching filer coupled to an origin server to provide storage virtualization of data served by the filer in response to data access requests issued by multi-protocol clients over a computer network. The multi-protocol caching filer includes a file system configured to manage a sparse volume that “virtualizes” a storage space of the data to thereby provide a cache function that enables access to data by the multi-protocol clients. To that end, the caching filer further includes a multi-protocol engine configured to translate the multi-protocol client data access requests into generic file system primitive operations executable by both the caching filer and the origin server.
摘要:
An architecture, including a file-level protocol, for supporting sparse volumes on a storage system is provided. The file-level protocol provides coherency checking for use in retrieving data stored on a backing store remote from a storage system.
摘要:
An architecture, including a file-level protocol, for supporting sparse volumes on a storage system is provided. The file-level protocol provides coherency checking for use in retrieving data stored on a backing store remote from a storage system.
摘要:
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.
摘要:
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.
摘要:
A system and method provides continuous data protection using checkpoints in a write anywhere file system. During a consistency point of a write anywhere file system, freed blocks are identified and are appended to a delete log for retention. A consistency point log is updated with a new entry associated with the consistency point. If the file system needs to retrieve its state at a particular point in time, the stored blocks of the delete log may be recovered.
摘要:
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.