摘要:
An extent-based storage architecture is implemented by a storage server receiving a read request for an extent from a client, wherein the extent includes a group of contiguous blocks and the read request includes a file block number. The storage server retrieves an extent identifier from a first sorted data structure, wherein the storage server uses the received file block number to traverse the first sorted data structure to the extent identifier. The storage server retrieves a reference to the extent from a second sorted data structure, wherein the storage server uses the retrieved extent identifier to traverse the second sorted data structure to the reference, and wherein the second sorted data structure is global across a plurality of volumes. The storage server retrieves the extent from a storage device using the reference and returns the extent to the client.
摘要:
An extent-based storage architecture is implemented by a storage server receiving a read request for an extent from a client, wherein the extent includes a group of contiguous blocks and the read request includes a file block number. The storage server retrieves an extent identifier from a first sorted data structure, wherein the storage server uses the received file block number to traverse the first sorted data structure to the extent identifier. The storage server retrieves a reference to the extent from a second sorted data structure, wherein the storage server uses the retrieved extent identifier to traverse the second sorted data structure to the reference, and wherein the second sorted data structure is global across a plurality of volumes. The storage server retrieves the extent from a storage device using the reference and returns the extent to the client.
摘要:
An extent-based storage architecture is implemented by a storage server. The storage server generates a new extent identifier for cloning a source extent identified by a source extent identifier and stored at a source data structure that includes a length value providing a length of the source extent, an offset value and a reference count value that provides a number of data containers that reference the source extent identifier. The storage server updates a data structure for a cloned version of the data container for storing the new extent identifier that points to the source extent identifier and includes an extent length value and offset value different from length value and the offset value of the source data structure.
摘要:
Overwriting part of compressed data without decompressing on-disk compressed data is implemented by receiving a write request for a block of data in a compression group from a client, wherein the compression group comprises a group of data blocks that is compressed, wherein the block of data is uncompressed. The storage server partially overwrites the compression group, wherein the compression group remains compressed while the partial overwriting is performed. The storage server determines whether the partially overwritten compression group including the uncompressed block of data should be compressed. The storage server defers compression of the partially overwritten compression group if the partially overwritten compression group should not be compressed. The storage server compresses the partially overwritten compression group if the partially overwritten compression group should be compressed.
摘要:
A request is received to remove duplicate data. A log data container associated with a storage volume in a storage server is accessed. The log data container includes a plurality of entries. Each entry is identified by an extent identifier in a data structures stored in a volume associated with the storage server. For each entry in the log data container, a determination is made if the entry matches another entry in the log data container. If the entry matches another entry in the log data container, a determination is made of a donor extent and a recipient extent. If an external reference count associated with the recipient extent equals a first predetermined value, block sharing is performed for the donor extent and the recipient extent. A determination is made if the reference count of the donor extent equals a second predetermined value. If the reference count of the donor extent equals the second predetermined value, the donor extent is freed.
摘要:
A request is received to remove duplicate data. A log data container associated with a storage volume in a storage server is accessed. The log data container includes a plurality of entries. Each entry is identified by an extent identifier in a data structures stored in a volume associated with the storage server. For each entry in the log data container, a determination is made if the entry matches another entry in the log data container. If the entry matches another entry in the log data container, a determination is made of a donor extent and a recipient extent. If an external reference count associated with the recipient extent equals a first predetermined value, block sharing is performed for the donor extent and the recipient extent. A determination is made if the reference count of the donor extent equals a second predetermined value. If the reference count of the donor extent equals the second predetermined value, the donor extent is freed.
摘要:
A system and method for managing data during consistency points in a storage system is provided. A buffer data control structure is modified to include a flags array that tracks various status flags for both a current and a next consistency point (CP). By utilizing multiple pointers within a buffer control structure, the storage system may permit write operations to continue to a data container undergoing write allocation. Received writes during a write allocation procedure are stored in raw data buffers and the buffer control structure is marked as being dirty for a next CP.
摘要:
A method of operating a storage system includes moving a block of data stored in the storage system to a new location in the storage system, such as for purposes of defragmentation. After the block has been moved to the new location, the storage system receives a request requiring access to the block. The storage system uses metadata appended to an identified block to detect that the block may have been relocated. The metadata can further be used to distinguish a block that has been relocated from a lost write.
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.