Abstract: One embodiment is related to a method for backing up a virtual disk file using parallel save streams, comprising: retrieving a block allocation table (BAT) of the virtual disk file; splitting the BAT into a plurality of split BATs; assigning data blocks of the virtual disk file to plexes based on the plurality of split BATs, wherein each plex corresponds to one of the plurality of split BATs; and streaming the plexes to a backup apparatus in parallel, wherein each plex occupies one stream.

Abstract: One embodiment is related to a method for encrypting a block based backup image file, comprising: preparing an unencrypted block based backup image file; determining whether a region of the unencrypted block based backup image file to be streamed to a backup medium corresponds to a block allocation table (BAT) region; streaming regions of the unencrypted block based backup image file determined as not corresponding to the BAT region unchanged to the backup medium; and encrypting regions of the unencrypted block based backup image file determined as corresponding to the BAT region before streaming the regions determined as corresponding to the BAT region to the backup medium.

Abstract: One embodiment is related to a method for backing up a shared volume using parallel save streams, comprising: taking a snapshot of the shared storage volume that is shared across a plurality of nodes; identifying used blocks on the shared storage volume based on the snapshot; organizing logically the used blocks into extent sets, wherein a number of extent sets is equal to a number of the plurality of nodes; assigning the extent sets to the plurality of nodes, wherein each of the plurality of nodes is assigned one extent set; and streaming, by each of the plurality of nodes, a respective extent set to a backup apparatus, wherein the plurality of nodes stream the extent sets in parallel.

Abstract: Native file system creation for backup files is described. A system creates a virtual disk template corresponding to a disk associated with a client device. The system sends a copy of the virtual disk template as template data. The system sends a copy of a file on the disk as file data. The system stores a backup file in a file system format that is native to the client device by combining the template data and the file data. The system restores a file in the backup file to the disk via mounting the backup file as a virtual disk on the client device.

Abstract: According to one embodiment, a restore module of a storage system receives a request from a client device over a network for restoring a data stream stored in the storage system. In response to the request, the restore module identifies a sparse disk file stored in the storage system, where the sparse disk file represents the requested data stream. The sparse disk file includes payload blocks sparsely located and intertwined with metadata of the sparse disk file. A converter executed in a memory by a processor of the storage system converts the sparse disk file into a native disk file based on the payload blocks of the sparse disk file, using a fast-copy method without having physically copying data content of the payload blocks. A block-based accessing interface is provided to the client to allow the client accessing the native disk file. Each block of content represented by the native disk is accessed based on a block identifier and an offset indicating a location of the block within the native disk file.

Abstract: According to one embodiment, analytics module of a storage system receives a request for analyzing a data stream stored in the storage system. In response to the request, the analytics module identifies a sparse disk file stored in the storage system representing the requested data stream. The sparse disk file includes payload blocks sparsely located and intertwined with metadata of the sparse disk file. A converter converts the sparse disk file into multiple native disk files based on the payload blocks of the sparse disk file, using a fast-copy method without having physically copying data content of the payload blocks. A block-based accessing interface is provided to allow multiple clients to concurrently access the native disk files, respectively. Each block of content represented by the native disk is accessed based on a block identifier and an offset indicating a location of the block within the native disk file.

Abstract: Techniques for determining characteristics of data blocks being accessed in a storage system are described herein. According to one embodiment, an input/output (IO) request is received for accessing a first data block of a first file stored in a storage system. The first file is one of the files stored in the storage system and each file contains multiple data blocks. In response to the request, a block-based monitor executed in a memory by a processor accesses a set of monitoring rules to determine whether the first file should be monitored. If so, the block-based monitor captures statistics data associated with the first data block and stores the statistics data of the first data block in a statistics database maintained in a persistent storage device. The statistics database stores statistics data of the data blocks of files monitored and captured based on the set of monitoring rules.