Abstract: A method, apparatus, and computer program product for reclaiming one or more chunks in a snapshot storage space, are disclosed. The method comprises detecting one or more unused chunks in the snapshot storage space in response to a predefined trigger event, and reclaiming one or more detected unused chunks by providing the one or more detected unused chunks to a storage pool for reuse. One or more unused chunks may be detected by scanning a first mapping table that records a storage state of a plurality of chunks in the snapshot storage space, and a determination made whether the one or more detected unused chunks have been reclaimed. If the one or more detected unused chunks have not been reclaimed, the one or more detected unused chunks may be provided to the storage pool and a second mapping table updated to record a reclaiming state of the one or more unused chunks. A new snapshot may be stored using a chunk in the snapshot storage space that has not been used and has not been reclaimed yet.

Abstract: Disclosed is an approach to implement a new layer of security within mobile devices using an encryption SDK, which implements a standalone component for applications to encrypt, decrypt, and view sensitive data on the device. A security layer is implemented on the device, wherein the security layer manages encryption for data retrieved onto the device from a cloud-based environment. Encrypted content is then generated at the security layer before storing the encrypted content by receiving the content object from the cloud-based environment and encrypting the content object with an encryption key that is password protected. The encrypted content is stored within an encrypted filesystem for presenting the content on the device.

Abstract: Embodiments described herein are related to cloning a volume in a file system. In some embodiments, a directory hard link is used to generate a clone of the root node of the volume. In certain embodiments, upon determining that a file or directory of the clone which comprises a hard link to an index node has been modified, a new object directory is generated beneath a root node of the volume. The index node may be added to the new object directory and one or more files and directories in the volume which link to the index node may be updated to contain symbolic links to the index node in the new object directory. In certain embodiments, a copy-on-write operation is performed in order to copy the file or directory and the new object directory to the clone.

Abstract: A system, method, and computer program product comprising receiving replicated IO direct to an image on a production site; wherein the replicated IO is a copy of IO for application to the image on the production site, storing the replicated IO in a differential structure in a journal, processing the IO on the image on the replication site, and periodically processing the differential structure to be become a differential snapshot; wherein the differential snapshot may be used by a hypervisor to provide instant access to the point in time corresponding to the differential snapshot.

Abstract: In some examples, a system may include multiple types of data restore point intervals, such as daily, weekly, monthly, etc. The system may store, for a first version of an object, a first time at which the object is received and a first flag for a first restore point interval. Subsequently, the system may store for a second version of the object, a second time at which the second object is received and a second flag for the first restore point interval. The system may clear a flag based on the second time and the first time being within a same time interval corresponding to the first restore point interval. An object version for which the flags have been cleared may be deleted from the storage. The stored times may be used to determine, at least partly, one or more retained object versions to provide for a selected restore point.

Abstract: An apparatus in one embodiment comprises a host device that includes at least one processor and an associated memory. The host device is configured to implement a plurality of containers each configured to access one or more portions of the memory. The containers are implemented as respective kernel control groups utilizing operating system level virtualization of the processor of the host device. The host device is further configured to assign the containers to groups in accordance with one or more designated criteria, and to generate checkpoints for respective groups of the containers. In conjunction with generation of a given one of the checkpoints for a particular one of the groups of containers, the host device identifies one or more pages of the memory that are shared by at least first and second containers of the particular group of containers, and generates the given checkpoint without duplicating the one or more shared pages to persistent storage.

Abstract: Techniques are provided for a linearizable primary-secondary database system that replicates database data with eventual consistency. The techniques include obtaining a logical clock value of a logical clock that orders transactions committed at a primary database system that includes a primary database. The logical clock value is obtained after a write transaction is committed at the primary database system and while processing a read request. The logical clock value is used to determine whether a secondary database is in a consistent replication state corresponding to the logical clock value with respect to the primary database. The read request is maintained in a linger state while the secondary database is not yet in the consistent replication state. The read request exits the linger state and is allowed to be processed against the secondary database after the secondary database has reached the consistent replication state.

Abstract: A computer-implemented method (500, 600, 700) and a system (210) for managing data according to a hierarchical data structure. The method allows storing data associated with a path and a file, the method comprising accessing the data; for at least one of path elements associated with the data, storing, in a hierarchy table (404) (i) a hierarchy identifier; (ii) an independent hierarchy table identifier; and (iii) a parent hierarchy table identifier. For at least one of the path elements and the file associated with the data, the method stores, in a file table (402), (i) an independent file table identifier; and (ii) a parent file table identifier associated with an independent file table identifier of a parent path element from which the at least one of the path elements and the file depends.

Abstract: A computer system including one or more processors and persistent, word-addressable memory implements a persistent atomic multi-word compare-and-swap operation. On entry, a list of persistent memory locations of words to be updated, respective expected current values contained the persistent memory locations and respective new values to write to the persistent memory locations are provided. The operation atomically performs the process of comparing the existing contents of the persistent memory locations to the respective current values and, should they match, updating the persistent memory locations with the new values and returning a successful status. Should any of the contents of the persistent memory locations not match a respective current value, the operation returns a failed status. The operation is performed such that the system can recover from any failure or interruption by restoring the list of persistent memory locations.

Abstract: An information management system according to certain aspects may be configured to generate a snapshot of data relating to a plurality of applications. The system may include a plurality of data agents, wherein each data agent is associated with at least one of a plurality of applications, and data generated by the plurality of applications is stored in a logical volume in primary storage. The system may also include a snapshot manager configured to detect the plurality of applications; check with the plurality of data agents whether the associated applications are in consistent states; obtain a snapshot of the logical volume in response to receiving notifications from the plurality of data agents that the associated applications are in consistent states; and generate mapping information between a particular one of the plurality of applications and a portion of the snapshot relating to the particular one of the plurality of applications.

Abstract: A chunk-based data deduplication system and method. Incoming data chunk is partitioned into head and tail portions for fingerprinting and mapping into respective head SHA (secure hash algorithm) and tail SHA tables. Head or tail fingerprints are used to locate predecessor data chunks almost identical to incoming data chunks and to determine data bursts to deduplicate the incoming data chunks.

Abstract: A method to identify data elements conforming to a policy includes receiving a request to identify data elements in an input set of data elements that conform to one or more requested policies. According to the method, policy output information describing data elements that conform to a requested policy are saved in association with the requested policy. In response to receiving a subsequent request to identify data elements in a subsequent set of data elements that conform to the requested policy, the method includes outputting the saved policy output information based on the policy output information having been saved in association with the requested policy. A computer program product and a system, configured with processors and a memory that can store saved policy information, can implement the method.

Abstract: One or more techniques and/or computing devices are provided for moving a consistency group having a replication relation. For example, a first consistency group of storage objects (e.g., files, logical unit numbers (LUNs), etc.) within first storage may have a replication relationship with a second consistency group within second storage (e.g., the second consistency group is maintained as a synchronously replicated copy of the first consistency group). A volume copy operation, a single file move on demand command, a single file restore command, or other functionality is used to move the first consistency group from the first storage to third storage, such as for load balancing, to create a moved first consistency group within the third storage. A new replication relationship is established between the moved first consistency group and the second consistency group, and the moved first consistency group and the second consistency group are resynchronized.

Abstract: A method and system for migrating data are described. A storage capture instance in a first format from a first type of device is received. Processing utilized to back up the storage capture instance to a second format of a snapshot tree is distributed to multiple storage nodes. A request to migrate at least part of the storage capture instance to a second type of device in a third format is received. In response to the request, processing utilized to migrate the at least part of the storage capture instance from the second format to the second type of device in the third format is distributed to the storage nodes. In one aspect, file(s) in a first network attached storage (NAS) device format are migrated to a second NAS device format. In another aspect, a virtual machine (VM) and/or file(s) therein having a first VM format are migrated to a second VM format.

Abstract: A system partitions a graph representation of relationships between block devices and associated snapshots into a plurality of cells to more evenly distribute computing resource usage attributable to the block devices and snapshots. The relationships may be analyzed to determine resource usage associated with the block devices and/or the snapshots wherein the resource usage corresponds to a mutation operation rate or number of mutation operations performed (or scheduled for performance). As a result of determining that the resource usage for a given cell exceeds a predetermined threshold for resource usage, the cell may be partitioned into a plurality of cells, and a portion of the corresponding block device(s), and subsequent snapshot(s) generated therefrom, may be assigned to the new cell.

Abstract: Systems, methods and apparatuses can present recovery of a log-structured file system. Embodiments can provide sending a request to a cloud store for backup data. The set of backup data received from the cloud store can comprise a set of data and metadata objects. The set of metadata objects can be read in a logical order. Each metadata object can be written from the set of data and metadata objects into block storage of the log-structured file system.

Abstract: A method and systems for monitoring changes for a server system are disclosed. The server system is operated on a first hardware system. Data is duplicated from the server system, and the data duplicated from the server system is transferred from the first hardware system on which the server system is operated, to a second hardware system separate from the first hardware system. The duplicated data is then processed on the second hardware system to determine a change for the server system. Present duplicated data transferred to the second hardware system may be compared to hosted data on the second hardware system, such as data previously duplicated from the server system. The server system may be a database server system.

Abstract: A time correction method, apparatus, and system, and relate to the field of communications technologies are provided. A virtual network function manager (VNFM) receives a hot migration notification message from a virtualized infrastructure manager (VIM) after hot migration is performed on a first virtual machine, where the hot migration notification message includes an identity (ID) of the first virtual machine; the VNFM searches, according to the ID of the first virtual machine, for a correspondence that is between an ID of a virtual machine and an identity of a service control virtual network function (VNF) and stored in the VNFM, to determine a first service control VNF; and the VNFM sends the hot migration notification message to the first service control VNF, where the hot migration notification message is used to instruct the first service control VNF to correct a system time of the first virtual machine.

Abstract: A method and systems for monitoring changes for a server system are disclosed. All data contents, for a first time point, of a dataset of the server system are obtained, and all data contents for a second time point of the dataset are also obtained. The first time point contents of the dataset are compared with the second time point contents of the dataset. The comparison is then used to determine a change for the server system between the first and second time points. The first time point contents of the dataset may be stored and, following the steps of comparing and using the comparison, a record of the change determined may be stored, and the stored first time point contents of the dataset discarded.

Abstract: One embodiment is related to a method for excluding files from a backup image file during a backup operation, comprising: determining files to be excluded from the backup image; taking a first snapshot of a source volume; exposing an iSCSI (Internet Small Computer System Interface) disk with the first snapshot being a target; deleting files to be excluded from the exposed iSCSI disk; taking a second snapshot of the exposed iSCSI disk; and streaming the second snapshot of the exposed iSCSI disk to create a save set in a virtual disk file on a backup medium.

Abstract: To maintain files in a retained file system, a run-time error detection code (EDC) is generated for a retained file. The run-time EDC is generated on the basis of at least one of entire content and metadata of the retained file. Further, the run-time EDC is compared with a validation EDC associated with the retained file to identify a corruption of the retained file. The validation EDC is generated at an instance of placing the retained file in the retained FS. Furthermore, the validation EDC is based on at least one of entire content and metadata of the retained file. Based on the comparison, an original version of the retained file may is restored from a trusted backup system.

Abstract: Methods and systems for generating a cluster consistent backup of a distributed, master-less database cluster is provided. One method includes a first phase of a backup operation where a crash consistent backup of the various LUNs used by the cluster nodes is taken. The crash consistent backup is then transformed into a cluster consistent backup during a second phase of the backup operation.

Abstract: Archiving local logical units of data storage (LUNs) to cloud storage, wherein the local LUNs reside on local physical storage of a data storage system, includes establishing a mirror between a local LUN and a cloud-backed LUN backed by cloud physical storage of a cloud storage system, the mirror making data contents of the cloud-backed LUN identical to data contents of the local LUN. Once the mirror is established, then (a) a stub is deposited on the local LUN to direct subsequent IOs to the cloud-backed LUN, and (b) local physical storage of the local LUN is released for allocation to other local LUNs. Subsequent IOs to the local LUN are satisfied from the cloud-backed LUN. An archived LUN can be restored by a restore process.

Abstract: A processing device stores a first log entry in a first log structure that stores log entries regarding occurrences of events for a first core in a computer system composed of a plurality of cores. In response to detecting the occurrence of a log flush trigger event, the processing device copies a plurality of log entries, including the first log entry, from the first log structure as a second log entry in a second log structure that stores log entries for multiple of the plurality of cores. The processing device dynamically determines the size of the second log entry based on the varied sizes of the plurality of log entries. The processing device generates a log entry header for the second log entry, including at least a core identifier identifying the first core associated with the first log structure and prepends the log entry header to the second log entry.

Abstract: The embodiments set forth techniques for generating snapshots of file system volumes without requiring the implementation of reference counts. A file system can manage snapshot identifiers (IDs) within an object map that corresponds to the file system volume, where each snapshot ID represents a different existing snapshot of the file system volume. A new snapshot can be generated simply by (1) establishing a new snapshot ID based on a current transaction ID managed for the file system volume, and (2) closing the current transaction ID and generating a new current transaction ID. In turn, the new current transaction ID is assigned as a transaction ID within mapping entries that are established/updated after the snapshot is established. In this manner, the transaction ID assigned to each mapping entry can be analyzed against the snapshot IDs to determine the snapshots (if any) to which the mapping entry corresponds.

Abstract: A system for providing high availability to persistent data is provided that persists data on a node in discrete partitions that are each backed up on separate backup systems. When the system detects that the data saved on the node is compromised, the system could restore the data from multiple backup systems. Since the backup systems hold discrete sets of data that do not overlap one another, the backup systems are able to simultaneously and locklessly restore data to the compromised node.

Abstract: Systems and methods enable a virtual machine, including any applications executing thereon, to quickly start executing and servicing users based on pre-staged data blocks supplied from a backup copy in secondary storage. An enhanced media agent may pre-stage certain backed up data blocks which may be needed to launch the virtual machine, based on predictive analysis pertaining to the virtual machine's operational profile. The enhanced media agent may also pre-stage backed up data blocks for a virtual-machine-file-relocation operation, based on the operation's relocation scheme. Servicing read requests to the virtual machine may take priority over ongoing pre-staging of backed up data. Read requests may be tracked so that the media agent may properly maintain the contents of an associated read cache. Some embodiments of the illustrative storage management system may lack, or may simply not require, the relocation operation, and may operate in a “live mount” configuration.

Abstract: Systems and methods are provided for data migration. The system may comprise one or more processors and a memory storing instructions that, when executed by the one or more processors, cause the system to migrate at least one first table of a first database schema to at least one second table of a second database schema, determine a query for modifying the first table during the migration, modify the second table based at least in part on the query, and update a mutation table to describe the modification, wherein the mutation table at least describes the modification.

Abstract: A method of controlling access to a flash memory device having multiple sectors divided into multiple blocks of memory, including accepting a virtual block address, calculating a set of possible sectors that can be used for storing data having the virtual block address based on a predefined function, reading meta-data of each sector from the set of possible sectors, wherein the meta-data of a sector includes information for each block in the sector indicating if the block is currently in use and the virtual block address of the data stored in the block, determining the physical block address of the virtual block address if the data is currently stored in a block in the possible sectors or if a block is currently allocated to store the data, wherein the set of possible sectors is distinct for each virtual block address.

Abstract: Systems and methods are disclosed for performing a backup of data to a backup server for one or more applications on a virtual machine having a universally unique identifier (UUID). A backup application can be deployed within the virtual machine, residing on a guest operating system. The backup application can report a list of applications on the virtual machine to the backup server. The backup server can deploy any application-specific modules that may be needed to perform the backup, and a list of pre- and post-backup actions to take, per application. The backup server can trigger the pre- and/or post-backup actions. The virtual machine can inform the backup server that the pre- and/or post-backup actions have completed. Backups can be in accordance with one or more policies stored at the backup server and associated with the virtual machine UUID or associated with an account that the virtual machine, or its user, are associated with.

Abstract: A virtual resource automatic selection system includes a setting unit that sets, for a plurality of pieces of training data composed of two or more parameters, a classification boundary between virtual resource clusters that are ranked in accordance with a capacity of a virtual resource in terms of a relationship between the two or more parameters. When a construction request for a new virtual network is received, a receiving unit receives information composed of the parameters. A determining unit determines to which of the virtual resource clusters the parameters belong. An allocating unit allocates a capacity of a virtual resource to the virtual network. An acquiring unit acquires network performance information from the virtual network. A second determining unit determines whether the network performance information satisfies a desired quality of service. The setting unit updates the classification boundary in accordance with a determination result of the second determining unit.

Abstract: A method for preventing data loss in target volumes of copy service functions is disclosed. In one embodiment, such a method includes detecting a copy service function that copies data from a source volume to a target volume. The method automatically creates, in a different address space than the source volume and target volume, a shadow volume to receive data overwritten on the target volume. The method further automatically establishes a point-in-time copy relationship between the target volume and the shadow volume to preserve data on the target volume as writes are received thereto. A corresponding system and computer program product are also disclosed.

Abstract: This application describes techniques for creating a second snapshot of a first snapshot of a set of data, modifying the first snapshot, and reverting the modifications to the first snapshot. For example, portions of one or more transaction logs may be played into a database to put the database in a particular state a particular point in time. The second snapshot may then be used to revert to a prior state of the database such that additional transaction logs may be played into the database. These techniques enable the ability to put the database into multiple states as the database existed at multiple points in time. Therefore, data can be recovered from the database as the data existed at different points in time. Moreover, individual data objects in the database can be accessed and analyzed as the individual data objects existed at different points in time.

Abstract: Example apparatus and methods provide a file system that stores files in multiple different logical units. The logical units are associated with different classes of devices. The file system interacts with the logical units through block-based interfaces. The file system is a single file system that spans the multiple logical units. The multiple different logical units include data storage devices for which the file system manages block storage allocation and an object storage system that manages its own block storage allocation rather than having the file system manage its block storage allocation. The file system may maintain a single namespace, hierarchy, or directory structure for the multiple logical units. The object storage system may protect files using redundant copies, erasure codes, or other approaches. An archive process may selectively move files from other devices to the object storage system and leave a symbolic link behind.

Abstract: Embodiments herein include methods and systems for use in delivering resources to a client device over a local network. An exemplary system comprises a plurality of caching devices operable to cache resources on behalf of a plurality of content providers, and a local caching device communicatively situated between an access network and the client device, wherein the access network is communicably situated between the plurality of caching devices and the local caching device. The local caching device is operable to retrieve a requested resource from at least one of the plurality of caching devices, deliver the requested resource to the client device over the local network, and store the requested resource for future requests by other client devices.

Abstract: Technologies for performing garbage collection in database systems, such as multi-version concurrency control (MVCC) database systems, are described. For example, different garbage collection techniques can be used separately or in various combinations, including interval garbage collection, group garbage collection, table garbage collection, and combinations. For example, a particular type of combination, called hybrid garbage collection, uses technique from interval garbage collection and group garbage collection, or from interval, group, and table garbage collection.

Abstract: A hyperconverged data storage system including a storage array. A first node includes hardware and a virtualization layer supporting guest virtual machines running first applications. An active first virtual storage controller executing in the first virtualization layer is configured for handling IOs accessing the storage array. A second node includes hardware and a second virtualization layer supporting guest virtual machines running second applications. A second virtual storage controller executing in the second virtualization layer operates in a standby mode to the first virtual storage controller. An internal communication network facilitates communications between the first node and the second node. The first virtual storage controller when operating in active mode is configured for handling IOs originating from the first applications and the second applications.

Abstract: Methods and systems are disclosed to initiate a snapshot of a volume distributed across a plurality of storage nodes of a distributed file system. The systems may create in the plurality of storage nodes a writeable sub-volume associated with the volume of the distributed file system. The system may identify a previous writeable sub-volume associated with a previous snapshot and mark the previous writeable sub-volume as read-only.

Abstract: As disclosed herein a computer program product for optimizing data synchronization when performing a block-level backup includes program instructions comprising instructions to receive a customized merging plan, create a padding map comprising missing data information, request missing data from a local backup server, wherein the instructions to request missing data comprise instructions to send the padding map to the local backup server, receive from the local backup server the missing data, and perform a snapshot consolidation according to the customized merging plan to provide a consolidated snapshot. The program instructions may include instructions to record missing data files and data blocks in the padding map. A computer system, corresponding to the computer program product is also disclosed herein.

Abstract: In one embodiment, a method includes replicating a production volume on a plurality of replica volumes. Each replica volume is stored on a respective storage array with a respective journal. The replicating includes writing data to a do stream of each journal written to the production volume, reading from the do stream of each journal, reading undo data that will be overwritten by the data in the do stream, distributing the undo data across the journals and writing the data from the do stream from each journal to the respective replica volume. A number of journals less than a total number of journals can be used to access data in a full journal.

Abstract: As disclosed herein, a method for optimizing data synchronization when performing a block-level backup includes receiving a customized merging plan, and creating a padding map that includes missing data information, and sending the padding map to a local backup server to request missing data. The method further includes receiving from the local backup server the missing data, and performing a snapshot consolidation according to the customized merging plan to provide a consolidated snapshot.

Abstract: A data replication method can begin with the detection of an inconsistency between records of a target table and corresponding records of a source table of a relational database management system (RDBMS) performing a parallel apply replication by an improved data replication manager. The target table can be a copy of the source table, both of which include multiple unique constraints and indexes. A timeframe that encompasses the records of the target table having the inconsistency can be determined. The timeframe can utilize a commit timestamp or a log sequence number. Consistency between the target table and the source table can be automatically restored for the determined timeframe through use of a reactive-apply process. Data suppression for updates is automatically restored once the copy is consistent. Transactions performed upon the target table by the reactive-apply process can be performed in parallel. Service at the source table and the target table can be uninterrupted.

Abstract: An application classifier classifies applications using latent semantic indexing (LSI) vectors of the applications. The application classifier uses a machine-learned model generated based on pairs of LSI vectors of positive and negative training sets of applications, where the positive training set includes applications within a desired category and the negative training set includes applications outside of the desired category. For a given application, the application classifier determines whether the application belongs to the desired category based on similarity of an LSI vector of the application and LSI vectors of positive and negative exemplar applications, as determined by the machine-learned model. If the LSI vector of the application is similar to an LSI vector of at least one positive exemplar application and not similar to an LSI vector of any of the negative exemplar applications, the application is determined to belong to the desired category.

Abstract: A method, a computing device, and a non-transitory machine-readable medium for replacing an unreadable sector in a storage system is provided. In some embodiments, the method includes identifying a sector from a plurality of sectors in a physical memory of a storage device in a storage system as an unreadable sector. An unreadable sector is a sector that includes data that had been corrupted and cannot be recovered from data in the storage system. In some embodiments, the unreadable sector is recovered by receiving a copy of a sector identified as the unreadable sector from a cloud storage, where the copy of the sector stores readable data and the cloud storage is a separate storage from the storage system. The method then includes replacing the unreadable sector with the copy at the sector at a memory location in the physical memory occupied by the unreadable sector.

Abstract: Systems, methods, and other embodiments associated with a synchronized test master are described. In one embodiment, a method periodically synchronizing test master data to a source database by, at a synchronization time: modifying the test master data to reflect changes to the source database since a last synchronization time; populating a transaction log with data manipulation operations performed on the source database since a last transaction time; and taking a snapshot of the test master data. Synchronization data is derived from the transaction log that includes a snapshot time for the snapshot and a modification time for each data manipulation operation in the transaction log. The method includes storing the synchronization data and snapshot for use in generating a test database that represents a point-in-time version of the source database.

Abstract: A process of obtaining, in effect, a multi-virtual-machine snapshot by taking a single-virtual-machine snapshot begins with creating, by a host hypervisor, a host virtual machine and a guest hypervisor. The guest hypervisor executes on the host virtual machine. Virtual machines to be included together in an effective multi-virtual-machine snapshot are migrated to the guest hypervisor. A single-virtual-machine snapshot is taken, by the host hypervisor, of the host virtual machine. The snapshot contains the state data for the virtual machines migrated to the guest hypervisor.

Abstract: A computer implemented method is provided. The method comprises initializing a first database image of a first database system based on a recovery image comprising committed transactions, visible uncommitted transactions, and undo logs associated with the visible uncommitted transactions, undoing the visible uncommitted transactions using the undo logs, generating redo logs from the undo logs, replaying the redo logs to create invisible uncommitted transactions, and after replaying the redo logs, replaying transaction logs received from a second database system. Related apparatus, systems, techniques and articles are also described.

Abstract: A set of snapshots are stored for a first object. The first object uses a first logical unit number (LUN) to store data. The snapshots correspond to points-in-time that the first object may be rolled back to. A request is received for a directed rollback of the first object to a second object. The request specifies a particular snapshot of the set of snapshots. The second object uses a second LUN, different from the first LUN to store data. After receipt of the request, a discovery map of the second object is dynamically created. The discovery map specifies a storage stack associated with the second object that maps the second object to a physical storage device accessed through the second LUN. The directed rollback to a point-in-time corresponding to the particular snapshot is performed by obtaining, from the discovery map, the storage stack associated with the second object.

Abstract: One embodiment provides a method for retrospective snapshot creation including creating, by a processor, a first snapshot that captures logical state of a data store at a first time in a time range. Creation of the first snapshot is based on determining existence of a second snapshot that captures logical state of the data store and recording a retrospective snapshot at a last valid log address offset prior to the first time upon a determination that the second snapshot exists based on determining at least one of: whether log address offsets from a first log entry of a log to a log entry of the log at the first time are contiguous and whether log address offsets from the second snapshot to the first time are contiguous.

Abstract: Systems and methods are disclosed for backing up a computer. The method includes choosing a time window to back up the computer; determining jobs that need to be synced during the time window and snapshots; determining an optimal set of snapshots that cover all jobs; altering job records in the database to point to one of the optimal snapshots; and deleting all snapshots not in the optimal set.