Abstract: Method and system for partially cloning a data container with compression is provided. A storage operating system determines if a portion of a source data container that is to be cloned includes a plurality of compressed blocks that are compressed using a non-variable compression group size. The operating system clones the plurality compressed blocks with the non-variable compression group size and de-compresses a plurality of blocks of the data container that are not within the non-variable compression group size. The plurality of compressed blocks and the plurality of blocks that are not within the non-variable compression group size are then stored as a partially cloned copy of the source data container.

Abstract: A data set on a physical storage device is associated with an active bitmap and a persistent point-in-time image (PPI) exclusion bitmap, where each bit in the bitmaps is associated with a data block in the data set. The active bitmap and the PPI exclusion bitmap are used to determine which of the data blocks in the data set are to be included in a PPI of the data set.

Abstract: A system and method for transparently compressing file system data using compression group descriptors is provided. When data contained within a compression group be compressed beyond a predefined threshold value, a compression group descriptor is included in the compression group that signifies that the data for the group of level 0 blocks is compressed into a lesser number of physical data blocks. When performing a read operation, the file system first determines the appropriate compression group that contains the desired data and determines whether the compression group has been compressed. If so, the file system decompresses the data in the compression group before returning the decompressed data. If the magic value is not the first pointer position, then the data within the compression group was previously stored in an uncompressed format, and the data may be returned without performing a decompression operation.

Abstract: 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.

Abstract: A method and apparatus is for outputting audio files to a user to enable selection of one of the audio files by the user. At least two independent audio files are played simultaneously, distributed differently over a set of speakers, thereby to appear to the user to originate from different directions. This enables a faster selection process by the user.

Abstract: A system and method are provided for estimating compressibility of data in a storage device. This is accomplished by actually running a compression algorithm on at least one data element in a storage device, without necessarily storing the compressed data. By this feature, the results of the compression may be compared with the original data element, to gauge an extent to which a compression algorithm is effective in compressing data in the storage device. To this end, in various embodiments, a user may be better able to estimate compression algorithm effectiveness before actually implementing the same.

Abstract: 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.

Abstract: A system and method for transparently compressing file system data using compression group descriptors is provided. When data contained within a compression group be compressed beyond a predefined threshold value, a compression group descriptor is included in the compression group that signifies that the data for the group of level 0 blocks is compressed into a lesser number of physical data blocks. When performing a read operation, the file system first determines the appropriate compression group that contains the desired data and determines whether the compression group has been compressed. If so, the file system decompresses the data in the compression group before returning the decompressed data. If the magic value is not the first pointer position, then the data within the compression group was previously stored in an uncompressed format, and the data may be returned without performing a decompression operation.

Abstract: A method and apparatus for retention of active data stored in memory using multiple indexing systems for data storage. An embodiment of a method for retention of active data in a storage server includes reading data into a first location of a main memory of the storage server. The data in the first location indexes data elements in a long-term data storage in a first manner. The method further provides for copying the data from the first location into a second location in the main memory of the storage server, where the data in the second location indexing the data elements in the long-term data storage in a second manner.

Abstract: The present invention provides a streaming media cache configured to select a timing interval, chosen from a set of one or more predetermined timing intervals, for each client that requests a data stream from the streaming media cache. Illustratively, clients requesting data streams below a predetermined bit rate (“bandwidth”) are assigned longer timing intervals than clients requesting data streams above the predetermined bit rate. More specifically, because the server can accommodate a larger number of relatively low-bandwidth clients than relatively high-bandwidth clients, the server selects timing intervals of longer duration for the relatively low-bandwidth clients so it may have more time to schedule send times for their requested packets.

Abstract: A method for mounting volumes to a storage server in a storage system, including, speeding up initialization of the storage server by staging volume mounting in two or more stages. The method further includes mounting at least one of the volumes when a request for accessing the volume is received.

Abstract: A storage server is configured to receive a request to store a data block from a client. The request to store the data block is serviced by the storage server by compressing the data block into a compression group which includes a number of compressed data blocks. The storage server stores the compression group in a non-volatile memory and flushes the compression group from the non-volatile memory to a physical storage device in response to reaching a consistency point. By compressing data to be stored in system memory of a storage servers the amount of data that can be processed during a given time period by a data storage system is increased.

Abstract: A storage server maintains an active file system and at least one read-only, persistent point-in-time image (RPPI) of the active file system. The booting time of the storage server is reduced by delaying the mounting of the RPPI(s) until the storage server receives a request to access a corresponding RPPI after the storage server has already booted.

Abstract: A method and system for estimating space in a compressed volume to enable a storage server to respond to write requests before actually compressing and/or allocating data on disk. In some embodiments, in response to receiving a request to store data, the storage server estimates the amount of storage space required to store the data on disk. The storage server compares the estimated amount with the amount of available disk space. When the amount of available disk space is less than the estimated space, the storage server sends a response indicating that the request failed. Otherwise, when the amount of available disk space is greater than or equal to the estimate space, the storage server sends a response indicating that the request succeeded. The response is sent before the storage server allocates any disk space in connection with the request.

Abstract: A method and system to efficiently transmit streaming media are described. The system includes a network protocol engine configured to receive a request for a data stream from a client system and to transmit data packets from the data stream to the client system; and a packet pacing sub-system, responsive to the request for the data stream. The packet pacing sub-system is configured to wait to receive a plurality of data packets from the data stream, and schedule delivery events for the plurality of data packets. The system may further include a streaming media protocol engine to determine a delivery time for data packets in the data stream. The packet pacing sub-system may be configured to receive an associated delivery time for the data packets from the streaming media protocol engine and schedule the delivery events for the data packets according to the associated delivery times for the plurality of packets.

Abstract: A technique for organizing data to facilitate data deduplication includes dividing a block-based set of data into multiple “chunks”, where the chunk boundaries are independent of the block boundaries (due to the hashing algorithm). Metadata of the data set, such as block pointers for locating the data, are stored in a tree structure that includes multiple levels, each of which includes at least one node. The lowest level of the tree includes multiple nodes that each contain chunk metadata relating to the chunks of the data set. In each node of the lowest level of the buffer tree, the chunk metadata contained therein identifies at least one of the chunks. The chunks (user-level data) are stored in one or more system files that are separate from the buffer tree and not visible to the user.

Abstract: A system and method for transparently compressing file system data using compression group descriptors is provided. When data contained within a compression group be compressed beyond a predefined threshold value, a compression group descriptor is included in the compression group that signifies that the data for the group of level 0 blocks is compressed into a lesser number of physical data blocks. When performing a read operation, the file system first determines the appropriate compression group that contains the desired data and determines whether the compression group has been compressed. If so, the file system decompresses the data in the compression group before returning the decompressed data. If the magic value is not the first pointer position, then the data within the compression group was previously stored in an uncompressed format, and the data may be returned without performing a decompression operation.

Abstract: A method and apparatus for retention of active data stored in memory using multiple indexing systems for data storage. An embodiment of a method for retention of active data in a storage server includes reading data into a first location of a main memory of the storage server. The data in the first location indexes data elements in a long-term data storage in a first manner. The method further provides for copying the data from the first location into a second location in the main memory of the storage server, where the data in the second location indexing the data elements in the long-term data storage in a second manner.

Abstract: A method and apparatus for retention of active data stored in memory using multiple indexing systems for data storage. An embodiment of a method for retention of active data in a storage server includes reading data into a first location of a main memory of the storage server. The data in the first location indexes data elements in a long-term data storage in a first manner. The method further provides for copying the data from the first location into a second location in the main memory of the storage server, where the data in the second location indexing the data elements in the long-term data storage in a second manner.

Abstract: A method and system for unified caching of media content are described. The system includes a streaming media protocol engine to receive a request for a data stream in a first format from a client system; a streaming media mass storage subsystem to locate the data stream stored by a cache server in a second format; and a network protocol engine to serve the located data stream to the client system in the first format.