Abstract: A key value (KV) store, a method thereof, and a storage system are provided herein. The KV store may include a key logger; and a processor configured to receive a first command for storing a first KV in the KV store, write a first value of the first KV to a first NAND page, generate an extent map for identifying the first memory page including the first value, write the extent map to a second memory page, append an entry for storing the first KV to the key logger, and update a device hashmap of the KV store to include a first key of the first KV, upon a threshold being met within the key logger.

Abstract: A key value (KV) store, a method thereof, and a storage system are provided herein. The KV store may include a key logger; and a processor configured to receive a first command for storing a first KV in the KV store, write a first value of the first KV to a first NAND page, generate an extent map for identifying the first memory page including the first value, write the extent map to a second memory page, append an entry for storing the first KV to the key logger, and update a device hashmap of the KV store to include a first key of the first KV, upon a threshold being met within the key logger.

Abstract: A system and method for storing data. In some embodiments, the method includes: receiving, by a persistent key-value storage device including a hash for mapping keys to value addresses, a first instruction, the first instruction being an instruction for accessing a first key, in a first key-value collection; and recording the first instruction in an instruction log of the persistent key-value storage device.

Abstract: A system and method for lifecycle-aware persistent key-value storage. In some embodiments, the method includes: receiving a first modification instruction, for a first key; incrementing a device write counter for a persistent storage device; selecting a first block, from the persistent storage device, for the first key, based on a current value of the device write counter; and storing the first key and an associated first value in the first block.

Abstract: A key value (KV) store, a method thereof, and a storage system are provided herein. The KV store may include a key logger; and a processor configured to receive a first command for storing a first KV in the KV store, write a first value of the first KV to a first NAND page, generate an extent map for identifying the first memory page including the first value, write the extent map to a second memory page, append an entry for storing the first KV to the key logger, and update a device hashmap of the KV store to include a first key of the first KV, upon a threshold being met within the key logger.

Abstract: A summary change log indexed by inode number is disclosed. An indication is received that a file system object associated with a corresponding file system index node (inode) has been modified. A summary change record is stored for the corresponding inode, including by: locating or creating an entry for the inode in an inode translation file; storing data associated with the modification in a summary change record located within a summary change file at an offset indicated in the entry; and using the summary change record to perform a backup.

Abstract: One example method includes reading a data chunk from a data stream, compressing the data chunk, and calculating a chunk delta. When the chunk delta is greater than zero, the compressed data chunk is appended to an incomplete data chunk. When the chunk delta is zero or less, the boundaries of a completed and compressed data chunk having a size at least as large as a minimum size are declared.

Abstract: One embodiment provides a computer implemented method of data identification within a deduplication storage system, the method comprising processing multiple units of a segment of data within the deduplication storage system using a fingerprint generation algorithm; storing the internal state generated while processing the multiple units of the segment of data; generating a first fingerprint for the segment of data based on the internal state; reloading the internal state after generating the first fingerprint for the segment of data; and generating a second fingerprint for the segment of data based on a transformed unit of the segment of data.

Abstract: One example method includes reading a data chunk from a data stream, compressing the data chunk, and calculating a chunk delta. When the chunk delta is greater than zero, the compressed data chunk is appended to an incomplete data chunk. When the chunk delta is zero or less, the boundaries of a completed and compressed data chunk having a size at least as large as a minimum size are declared.

Abstract: Techniques to back up data are disclosed. In various embodiments, a copy of a free block map as of a first time associated with a first backup is stored in persistent data storage. Writes made subsequent to the first backup to blocks not listed as free in the copy of the free block map as of the first time are tracked in a persistently-stored change block tracking log. A free block map as of a second time and the previously-stored copy of the free block map as of the first time are used to determine which blocks listed as free in the free block map as of the first time have been written to since the first time. At least a subset of blocks determined to have been written to since the first time are including in an incremental backup.

Abstract: Techniques to back up data are disclosed. In various embodiments, a copy of a free block map as of a first time associated with a first backup is stored in persistent data storage. Writes made subsequent to the first backup to blocks not listed as free in the copy of the free block map as of the first time are tracked in a persistently-stored change block tracking log. A free block map as of a second time and the previously-stored copy of the free block map as of the first time are used to determine which blocks listed as free in the free block map as of the first time have been written to since the first time. At least a subset of blocks determined to have been written to since the first time are including in an incremental backup.

Abstract: A cloud storage system stores data objects from different customers. Each customer has their own encryption key to encrypt the data objects for storage and the key is not shared. To deduplicate the data objects, a set of base fingerprints associated with a set of base data objects is stored. A first fingerprint associated with a data object from a customer is compared with a base fingerprint. The first and base fingerprints are generated by applying an identical fingerprinting algorithm to unencrypted versions of the data objects. If the fingerprints match, the first fingerprint is associated with a base data object corresponding to the matching base fingerprint, and the data object from the customer is not stored. If the fingerprints do not match, the data object from the customer is stored.

Abstract: Techniques to back up data are disclosed. In various embodiments, a copy of a free block map as of a first time associated with a first backup is stored in persistent data storage. Writes made subsequent to the first backup to blocks not listed as free in the copy of the free block map as of the first time are tracked in a persistently-stored change block tracking log. A free block map as of a second time and the previously-stored copy of the free block map as of the first time are used to determine which blocks listed as free in the free block map as of the first time have been written to since the first time. At least a subset of blocks determined to have been written to since the first time are including in an incremental backup.

Abstract: Techniques to back up data are disclosed. In various embodiments, a copy of a free block map as of a first time associated with a first backup is stored in persistent data storage. Writes made subsequent to the first backup to blocks not listed as free in the copy of the free block map as of the first time are tracked in a persistently-stored change block tracking log. A free block map as of a second time and the previously-stored copy of the free block map as of the first time are used to determine which blocks listed as free in the free block map as of the first time have been written to since the first time. At least a subset of blocks determined to have been written to since the first time are including in an incremental backup.

Abstract: A computer-implemented method for enhancing data transfer is disclosed. The method starts with capturing a snapshot of a storage volume and creating a snapshot volume in response to receiving a request for backing up data from the storage volume of a storage system. Upon receiving a write request for writing a new block to a block location of the storage volume while the storage system is performing a backup operation from the snapshot volume to a target storage system, the storage system performs data preservation for the block location only if the block location to be written is not free, otherwise the new block is written to the block location of the storage volume based on the write request without preservation.

Abstract: Techniques to back up data are disclosed. In various embodiments, a copy of a free block map as of a first time associated with a first backup is stored in persistent data storage. Writes made subsequent to the first backup to blocks not listed as free in the copy of the free block map as of the first time are tracked in a persistently-stored change block tracking log. A free block map as of a second time and the previously-stored copy of the free block map as of the first time are used to determine which blocks listed as free in the free block map as of the first time have been written to since the first time. At least a subset of blocks determined to have been written to since the first time are including in an incremental backup.

Abstract: Techniques to back up data are disclosed. In various embodiments, a copy of a free block map as of a first time associated with a first backup is stored in persistent data storage. Writes made subsequent to the first backup to blocks not listed as free in the copy of the free block map as of the first time are tracked in a persistently-stored change block tracking log. A free block map as of a second time and the previously-stored copy of the free block map as of the first time are used to determine which blocks listed as free in the free block map as of the first time have been written to since the first time. At least a subset of blocks determined to have been written to since the first time are including in an incremental backup.

Abstract: A method for file system checking in a storage device. The method includes executing a computer system having a plurality microprocessor cores, initiating a file system check operation by using a file system check agent that execute on the computer system and accesses a storage device, and validating a plurality of meta-data structures of the file system. The method further includes dividing and allocating the metadata structures among a plurality of worker threads. For each worker thread, data corresponding to the metadata structures is processed using a read ahead operation. file system check is processed to completion, wherein the read ahead operation feeds data corresponding to the metadata structures to each of the plurality of worker threads in parallel.

Abstract: Block-based backups for sub-file modifications are described. A system records an identifier of a modified file into a file modification journal. The system records an identifier corresponding to a modified block in a file system into a modified block map. The system creates a modified file block map based on the identifier of the modified file in the file modification journal. The system identifies a modified file block corresponding to the modified file based on an intersection of the modified block map and the modified file block map. The system reads the modified file block from the file system using a file system read interface. The system writes the modified file block to a backup storage.

Abstract: File-based snapshots for block-based backups are described. A system records an identifier corresponding to a modified block in a file system into a modified block map. The system creates a modified file block map based on a modified file. The system identifies a modified file block corresponding to the modified file based on an intersection of the modified block map and the modified file block map. The system creates a mounted backup image by mounting a previously created block-based backup of the file system onto a proxy host. The system enables a forward snapshot of the mounted backup image. The system reads the modified file block from the file system using a file system read interface. The system creates a forward snapshot file for the modified file by writing the modified file block to the mounted backup image using a file system write interface.