Abstract: A backup management system may include a data management server, a warm-tier data store, and a cold-tier data store. Snapshots may be captured from various client devices. A data block stored in the warm-tier data store may be referenced by multiple backup snapshots and/or referenced by one or more users. When a data block's total reference count is equal to the cold reference count or equal to or less than a threshold total reference count, the data management server may determine that the data block is ready to be migrated to the cold-tier data store. The data management server may send the data block into a candidate queue. In the queue, data blocks with similar retention periods or similar expected restoration may be grouped as a unit. The unit may be transmitted to the cold-tier data store in a single write request.

Abstract: A system for dynamic file chunking is provided. The system includes a memory and a processor configured to access one or more files to be chunked for a data backup operation and to identify a type of the one or more files. The type of the file is based upon an extension of the respective file. The processor is configured to analyze storage data associated with each type of files corresponding to a plurality of chunking techniques. The processor is configured to associate each of files with a corresponding data chunk size and a chunking technique class based upon the analyzed storage data and to analyze data backup parameters in-real time during the data backup operation and to update at least one of the data chunk size and the chunking technique for each of the type of files based upon the data backup parameters.

Abstract: A file system and a related method are presented. The file system includes an object storage configured to store file data for one or more files and a plurality of namespace entries corresponding to file data and/or metadata of the one or more files as one or more objects. Each namespace entry of the plurality of namespace entries includes an operation type conducted on the file data and/or metadata captured in a particular snapshot and a version number corresponding to the particular snapshot. The file system further includes an indexing system configured to generate the plurality of namespace entries; store the plurality of namespace entries as one or more objects in the object storage; and identify, in response to a search query, one or more files for retrieval from the object storage based on a list of the plurality of namespace entries sorted on the version numbers.

Abstract: A data management system may maintain a total-size counter for the file system. The total-size counter represents a sum of data size related to snapshots backed up to the file system. The data management system may perform data operation cycles to the file system. Each data operation cycle corresponds to a snapshot that includes files. Each data operation cycle may include incrementing the total-size counter by the data size of the files in the snapshot exchanged with the file system and adding, to a snapshot record, the amount of increment in incrementing the total-size counter as an increment-size counter. A data management system may perform a correction operation to correct the total-size counter. The correction operation may change the total-size counter by a difference between the total of the increment-size counters in the snapshot records and the total data size of file data exchanged with the file system.

Abstract: A file system and a related method are presented. The file system includes a data storage including a plurality of data blocks; a merge index including a plurality of namespace entries, wherein the plurality of namespace entries include a plurality of blockmap entries and a plurality of local reference entries; a deduplication database including a plurality of deduplication indices and a plurality of global reference entries for a plurality of datasets; and an indexing system configured to generate the plurality of namespace entries and the plurality of global reference entries.

Abstract: A file system and a related method are presented. The file system includes a data storage including a plurality of data blocks; a merge index including a plurality of namespace entries, wherein the plurality of namespace entries include a plurality of blockmap entries and a plurality of local reference entries; a deduplication database including a plurality of deduplication indices and a plurality of global reference entries for a plurality of datasets; and an indexing system configured to generate the plurality of namespace entries and the plurality of global reference entries.

Abstract: A file system may include an object storage, a merged index, and a distributed database. When a file is stored in the file system, the file may be converted to an object and be stored in the object storage. The deduplication index of the file may be stored in the distributed database. The namespace metadata of the file may be stored in the merged index. The merged index generates namespace entries of the file when the file is created, deleted, and/or modified. A namespace entry may be associated with a specific file and may include a creation version and a deletion version. When a file is deleted or modified, instead of modifying the existing namespace entries, new entries associated with different versions and including different creation or deletion versions are created. The status of a file may be monitored by one or more entries associated with a file.

Abstract: A data restoration system including a data management server. The data management server receives one or more data restoration requests for restoring a plurality of data blocks. The data management server determines, based on metadata associated with the data blocks, a first subset of warm data blocks corresponding to warm-tier data and a second subset of cold data blocks corresponding to cold-tier data. The data management server retrieves the warm data blocks in the first subset and restores the warm data blocks in the first subset. The data management server groups the cold data blocks based in part on storage times of the cold data blocks to generate a plurality of cold-tier data retrieval requests. The data management server retrieves the cold data blocks by batches, each batch corresponding to one of the cold-tier data retrieval requests. The data management server restores the cold data blocks in the second subset.

Abstract: Methods and devices for assessing the quality of user-generated content are described. In one embodiment, a method is disclosed for measuring the quality of a user-generated answer to a question by combining various factors, including question-answer surface word vector similarity, question-answer explicit semantic analysis vector similarity, answer-answer explicit sematic analysis vector similarity, query performance predictor, sentiment analysis, textual analysis of the answer, and reputation of the answerer. The method uses a learning procedure to determine the best algorithm for measuring the overall quality of the answer based on these factors.

Abstract: A system for data backup is provided. The system includes a memory having computer-readable instructions stored therein and a processor configured to execute the computer-readable instructions to receive a request for full data and/or incremental backup for a volume and to perform a full backup of the volume based on a first block size in response to a full data backup request. The processor is configured to generate a digital fingerprint of the full backup and determine if the full backup exists on a backup media based on the generated digital fingerprint and to upload the full backup to the backup media if it is determined that the first backup is unavailable on the backup media and perform an incremental backup of the volume based on a second block size in response to an incremental backup request. The second block size is substantially smaller than the first block size.

Abstract: A data back-up system configured to back-up one or more data sets from one or more devices to a data back-up server by using a proxy pool is presented. The data back-up system includes a load-balancer configured to distribute the one or more data sets across the proxy pool. The load balancer includes a data receiver configured to receive types of files, number of files, and total size of each file in the one or more data sets; a load estimator configured to estimate a weighted average load of each data set based on the number of files, the total size of each file, a compressibility factor for each file type, and an encryption factor for each file type; and a load distributor configured to distribute the one or more data sets as a plurality of workloads across the proxy pool.

Abstract: A data restoration system including a data management server. The data management server receives one or more data restoration requests for restoring a plurality of data blocks. The data management server determines, based on metadata associated with the data blocks, a first subset of warm data blocks corresponding to warm-tier data and a second subset of cold data blocks corresponding to cold-tier data. The data management server retrieves the warm data blocks in the first subset and restores the warm data blocks in the first subset. The data management server groups the cold data blocks based in part on storage times of the cold data blocks to generate a plurality of cold-tier data retrieval requests. The data management server retrieves the cold data blocks by batches, each batch corresponding to one of the cold-tier data retrieval requests. The data management server restores the cold data blocks in the second subset.

Abstract: A system identifies and causes transmission of differential data generated during device migration. An administrative server accesses a first backup snapshot of a retiring client device. The first backup snapshot includes a set of files stored in the retiring client device during a first checkpoint. The administrative server transmits the set of files in the first backup snapshot to a replacement client device. A cloud server stores the first backup snapshot and a second backup snapshot of the retiring client device. The second backup snapshot is created during a second checkpoint occurring after transmission of the set of files. The cloud server receives an indication that a user has logged on to the replacement client device and causes a transmission of differential data to the replacement client device. The differential data includes at least one file in the second backup snapshot that is not included in the first backup snapshot.

Abstract: A file system may include an object storage, a merged index, and a distributed database. When a file is stored in the file system, the file may be converted to an object and be stored in the object storage. The deduplication index of the file may be stored in the distributed database. The namespace metadata of the file may be stored in the merged index. The merged index generates namespace entries of the file when the file is created, deleted, and/or modified. A namespace entry may be associated with a specific file and may include a creation version and a deletion version. When a file is deleted or modified, instead of modifying the existing namespace entries, new entries associated with different versions and including different creation or deletion versions are created. The status of a file may be monitored by one or more entries associated with a file.

Abstract: A file system may include an object storage, a merged index, and a distributed database. When a file is stored in the file system, the file may be converted to an object and be stored in the object storage. The deduplication index of the file may be stored in the distributed database. The namespace metadata of the file may be stored in the merged index. The merged index generates namespace entries of the file when the file is created, deleted, and/or modified. A namespace entry may be associated with a specific file and may include a creation version and a deletion version. When a file is deleted or modified, instead of modifying the existing namespace entries, new entries associated with different versions and including different creation or deletion versions are created. The status of a file may be monitored by one or more entries associated with a file.

Abstract: A proactive data recovery system is provided. The system includes a memory having computer-readable instructions stored therein and a processor configured to execute the computer-readable instructions to access a data storage platform and to monitor a plurality of parameters indicative of a requirement of data restore and/or recovery for the data storage platform. The requirement corresponds to a predicted occurrence of a disaster event. The processor is further configured trigger backup of data stored in the data storage platform based upon the plurality of parameters to create a restore package and to initiate the data restore and/or data recovery operation for the data storage platform using the restore package in response to the occurrence of the disaster event.

Abstract: System for delivering an event journal during a back-up session in a distributed file system is presented. The system includes an event intake module, a load balancer, a plurality of object creation modules, a journal manager, and a journal service module. Each object creation module of the plurality of object creation modules further includes an ingestor and a drainer. A related method is also presented. The system and method provide for reliable and time-ordered delivery of events in the event journal.

Abstract: A system identifies and causes transmission of differential data generated during device migration. An administrative server accesses a first backup snapshot of a retiring client device. The first backup snapshot includes a set of files stored in the retiring client device during a first checkpoint. The administrative server transmits the set of files in the first backup snapshot to a replacement client device. A cloud server stores the first backup snapshot and a second backup snapshot of the retiring client device. The second backup snapshot is created during a second checkpoint occurring after transmission of the set of files. The cloud server receives an indication that a user has logged on to the replacement client device and causes a transmission of differential data to the replacement client device. The differential data includes at least one file in the second backup snapshot that is not included in the first backup snapshot.

Abstract: A system for data backup is provided. The system includes a memory having computer-readable instructions stored therein and a processor configured to execute the computer-readable instructions to receive a request for full data and/or incremental backup for a volume and to perform a full backup of the volume based on a first block size in response to a full data backup request. The processor is configured to generate a digital fingerprint of the full backup and determine if the full backup exists on a backup media based on the generated digital fingerprint and to upload the full backup to the backup media if it is determined that the first backup is unavailable on the backup media and perform an incremental backup of the volume based on a second block size in response to an incremental backup request. The second block size is substantially smaller than the first block size.

Abstract: A system for dynamic file chunking is provided. The system includes a memory and a processor configured to access one or more files to be chunked for a data backup operation and to identify a type of the one or more files. The type of the file is based upon an extension of the respective file. The processor is configured to analyze storage data associated with each type of files corresponding to a plurality of chunking techniques. The processor is configured to associate each of files with a corresponding data chunk size and a chunking technique class based upon the analyzed storage data and to analyze data backup parameters in-real time during the data backup operation and to update at least one of the data chunk size and the chunking technique for each of the type of files based upon the data backup parameters.