Abstract: One example method includes performing delta operations to protect data. During a delta operation, a primary map and a secondary map are processed using bit logic. The bit logic determines how to handle data stored at a location on the volume associated with an entry in the primary map and included in the current delta operation when a new write for the same location is received as the corresponding entry in the primary map is processed.

Abstract: A node synchronization method and apparatus, an electronic device, and a computer-readable storage medium, include: acquiring node data sent by each slave node; obtaining a target cluster parameter from each piece of node data, and obtaining a standard cluster parameter by using the target cluster parameter based on an event queue length; determining an authorized slave node according to the standard cluster parameter, and judging whether a quantity of authorized slave nodes is greater than a quantity threshold; and if the quantity is greater than the quantity threshold, performing event playback on the authorized slave node by using a cluster event based on the standard cluster parameter; or if the quantity is not greater than the quantity threshold, controlling the authorized slave node to perform status synchronization on an unauthorized slave node, and performing event playback on the authorized slave node by using a cluster event after status synchronization.

Abstract: A method includes, responsive to a SET command associated with a key-value store, concurrently updating the key-value store maintained on a non-persistent memory device of a memory sub-system and a mirror of the key-value store maintained on a persistent memory device of the memory sub-system. The method further includes responsive to a GET command associated with the key-value store, retrieving a value of a key from the key-value store maintained on the non-persistent memory device.

Abstract: Provided is a unit comprising a DMAC which, on the basis of a signal outputted from a time counting part which operates in synchronization with a time counting part of a PLC, does not communicate a memory via a serial bus in a control cycle of a CPU during at least a first period overlapping a period in which the CPU communicates with the memory, and communicates with the memory via the serial bus during a second period which begins after the first period.

Abstract: A computer-implemented method includes migrating an item to a cache cluster from a home cluster in a storage system in a cutover process and initiating a data validation process with the home cluster. The method includes enabling at least one tunable parameter on the item on the cache cluster in the storage system. The tunable parameter is configured to adjust the data validation process with the home cluster. The tunable parameter includes at least one condition. The method includes enabling at least one flag on the item on the cache cluster in the storage system. The flag is configured to indicate that the at least one condition of the tunable parameter on the item in the storage system is met. In response to the at least one condition of the tunable parameter being met, the method includes ending the data validation process with the home cluster in the storage system.

Abstract: An address range mirroring system includes a plurality of processing subsystem/memory subsystem nodes that each include a respective processing subsystem coupled to a respective memory subsystem, an operating system provided by at least one of the plurality of processing subsystem/memory subsystem nodes, and a Basic Input/Output System (BIOS) that is coupled to the plurality of processing subsystem/memory subsystem nodes. The BIOS identifies an address range mirroring memory size that was provided by the operating system, and an address range mirroring node usage identification that was provided by the operating system. The BIOS then configures address range mirroring according to the address range mirroring memory size in the respective memory subsystem in each of a subset of the plurality of processing subsystem/memory subsystem nodes, with the subset of the plurality of processing subsystem/memory subsystem nodes based on the address range mirroring node usage identification.

Abstract: A computer-implemented method in a computing network of a number of processing nodes 1 to X, in the computing network neurons of a Convolutional Neural Network (CNN) are divided between the number of nodes. The method including allocating a mini-batch of input data from among mini-batches of input data to a node of the nodes; splitting the mini-batch into a number of mini-batch sections X corresponding and equal to the number of nodes; at the node retaining a mini-batch section which has a same number as the node and sending other mini-batch sections of the split mini-batch sections to corresponding other nodes according to a number of the split mini-batch sections; collating at the node the split mini-batch sections at the node into a single matrix and multiplying the collated matrix by the neurons to provide output data sections having one section of output data per each mini-batch.

Abstract: Certain aspects of the present disclosure generally relate to wireless communications and, more particularly, to methods and apparatus for segmenting uplink control information prior for encoding using a polar code prior to transmission. An exemplary method that may be performed by a wireless device generally includes iteratively segmenting a group of K information bits into a plurality of segments, encoding the information bits of each of the plurality of segments using a polar code to generate a plurality of encoded segments, and transmitting the plurality of encoded segments.

Abstract: The present disclosure generally relates to creating virtualized block storage devices whose data is replicated across isolated computing systems to lower risk of data loss even in wide-scale events, such as natural disasters. The virtualized device can include at least two volumes, each of which is implemented in a distinct computing system. Each volume can be implemented by at least two computing devices, a first of which is configured as a primary device to which reads from and writes to the volume are directed. Of the two volumes, one can be indicated as primary, indicating authority to accept reads to and writes from the virtualized device. A primary device of the primary volume, on obtaining a write to the volume, can replicate the write to both a secondary device of a primary volume and to the secondary volume.

Abstract: A memory controller includes a meta data memory configured to store mapping information of data stored in a plurality of memory blocks included in a memory device and valid data information indicating whether the data stored in the plurality of memory blocks is valid data, and a migration controller configured to control the memory device to perform a migration operation of moving a plurality of valid data stored in a source memory block among the plurality of memory blocks from the source memory block to a target memory block based on the mapping information and the valid data information.

Abstract: A secondary storage controller determines one or more tracks of one or more volumes in which data loss has occurred in the secondary storage controller. The secondary storage controller suspends a peer to peer remote copy operation between the secondary storage controller and a primary storage controller. Information on the one or more tracks of the one or more volumes in which the data loss has occurred is transmitted to the primary storage controller.

Abstract: In some examples, a system receives a command for an operation involving a storage system, compares attributes associated with the command to a signature, the signature based on a storage volume characteristic and a configuration of the storage system, and responsive to the comparison of the attributes associated with the command to the signature, indicates a potential fault associated with the operation indicated by the command.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for resynchronizing data in a storage system. One of the methods includes determining that a particular disk of a capacity object of a storage system was offline for an interval of time, wherein the capacity object comprises a plurality of segments, and wherein the storage system comprises a segment usage table identifying a linked list of particular segments of the capacity object that are in use; determining a time point at which the particular disk went offline; determining one or more first segments of the capacity object that were modified after the time point, wherein determining one or more first segments comprises determining each segment of the segment usage table having a transaction ID that is larger than the time point; and resynchronizing, for each first segment, a portion of the particular disk corresponding to the first segment.

Abstract: An illustrative ISCSI server computing device provides user computing devices with “private writable snapshots” of a desired volume of data and/or further provides “private writable backup copies.” The ISCSI service is provided without invoking snapshot limits imposed by storage arrays and further without specialized backup software and pseudo-disk drivers installed on the user computing devices. A user can browse as well as edit personal versions of any number and/or versions of block-level backup copies—the “private writable backup copies.” Likewise, a user can browse and edit personal versions of any number of snapshots of one or more versions of one or more desired data volumes—the “private writable snapshots.” A user can have any number of co-existing private writable snapshots and private writable backup copies. Sparse files, extent-files, software snapshots, and/or media agents co-residing on the ISCSI server are used in the illustrative embodiments.

Abstract: A system and method for facilitating a migration engine to migrate data items in a data directory from a source system to a destination system over multiple migration passes are disclosed. A state file can be used to track migration states of data items during the life cycle of the migration. The state file can be generated and updated by a plugin to the migration engine. During a migration pass, the state file can be loaded into the memory to influence the migration by the migration engine. Prior to the migration pass, migration profile specifying one or more migration actions can be invoked by a migration routine. The invocation of the migration profile can cause the state file to be modified to perform the migration actions accordingly.

Abstract: A distributed, web-services based storage system. A system may include a web services interface configured to receive, according to a web services protocol, a given client request for access to a given data object, the request including a key value corresponding to the object. The system may also include storage nodes configured to store replicas of the objects, where each replica is accessible via a respective unique locator value, and a keymap instance configured to store a respective keymap entry for each object. For the given object, the respective keymap entry includes the key value and each locator value corresponding to replicas of the object. A coordinator may receive the given client request from the web services interface, responsively access the keymap instance to identify locator values corresponding to the key value and, for a particular locator value, retrieve a corresponding replica from a corresponding storage node.

Abstract: Methods and the like according to the disclosure can include determining an information type of digital information, writing the digital information using a first process (in response to a determination that the information type of the digital information is a first information type), and, in response to a determination that the information type of the digital information is a second information type, determining erasure-coded parity information for the digital information and writing the digital information using a second process (where the digital information is to be written to erasure-coded storage). In the former case, the first process that includes writing the digital information to storage. The second process includes writing the digital information and the erasure-coded parity information to erasure-coded storage, without writing the digital information to a log.

Abstract: A computing system that receives and stores configuration information for the application in a data store. The configuration information comprises (1) identifiers for a plurality of cells of the application that include at least a primary cell and a secondary cell, (2) a defined state for each of the plurality of cells, (3) one or more dependencies for the application, and (4) a failover workflow defining actions to take in a failover event. The computing system receives an indication, from a customer, of a change in state of the primary cell or a request to initiate the failover event. The computing system updates, in the data store, the states for corresponding cells of the plurality of cells based on the failover workflow and updates, in the data store, the one or more dependencies for the application based on the failover workflow.

Abstract: The present disclosure relates to a method, device and program product for managing an access request in a storage system. In the method, based on an access request to the storage system, an address range of a data object involved in the access request is obtained. An access type of the access request is identified in accordance with determining that a garbage collection operation is performed on a data extent within the address range. The access request is responded to based on the access type by using a data extent within an address range in the storage system on which no garbage collection operation is performed.

Abstract: Embodiments for performing data recovery from cloud storage to a backup appliance that goes from an offline state to an online state, including identifying super metadata among metadata stored in the cloud storage for the backup appliance, wherein the super metadata comprises an amount on the order of ten percent of the metadata representing a minimum amount of information to reconstruct the metadata, copying the super metadata blocks from the cloud storage to local metadata storage of the backup appliance while it is in the offline state to leave remaining metadata, and copying the remaining metadata blocks from the cloud storage to the local metadata storage while the backup appliance is in the online state.

Abstract: An address range mirroring system includes a plurality of processing subsystem/memory subsystem nodes that each include a respective processing subsystem coupled to a respective memory subsystem, an operating system provided by at least one of the plurality of processing subsystem/memory subsystem nodes, and a Basic Input/Output System (BIOS) that is coupled to the plurality of processing subsystem/memory subsystem nodes. The BIOS identifies an address range mirroring memory size that was provided by the operating system, and an address range mirroring node usage identification that was provided by the operating system. The BIOS then configures address range mirroring according to the address range mirroring memory size in the respective memory subsystem in each of a subset of the plurality of processing subsystem/memory subsystem nodes, with the subset of the plurality of processing subsystem/memory subsystem nodes based on the address range mirroring node usage identification.

Abstract: A database server includes a database manager and a synchronization processing unit. When the database server is in a first state in which the database server receives requests from a client, the database manager updates a database in accordance with a request from the client and registers both update data for causing another database server included in the plurality of database servers to update a database of the other database server and management information of the update data for each data management unit in a memory on the basis of the request. When the database server is in the first state, the synchronization processing unit transmits the update data registered in the memory to the other database.

Abstract: The present invention provides a data write method and a solid-state drive array. The solid-state drive array is based on a RAID system and includes n solid-state drives. Before to-be-written data is written into the solid-state drive array, the to-be-written data is divided into n data blocks that are in a one-to-one correspondence with the n solid-state drives. After the n data blocks are all stored into the corresponding solid-state drives, FTL update of the n data blocks is performed, to complete write of the to-be-written data. If the solid-state drive array is powered off during storage of the n data blocks, because FTL update of the data blocks is not performed, all the n data blocks fail to be written into the solid-state drive array, thereby ensuring atomicity of write operations of the n data blocks.

Abstract: A system and method for managing a storage system may include generating, for a data block, a set of tags and a unique name. A set of tags may represent a context. A service related to the data block may be provided in response to receiving at least one of: a tag, a set of tags and a unique name.

Abstract: Techniques for storage management involve: detecting a trigger for an adjustment of a redundant level for a set of RAIDs. Each of the set of RAIDs includes one or more RAID extents. Each RAID extent is formed by a plurality of storage extents from a set of storage extents. The set of storage extents is obtained by dividing a plurality of storage disks into storage extents. The plurality of storage extents are located in different storage disks of the plurality of storage disks. The techniques further involve: in response to detecting the trigger, selecting, from the set of RAIDs, a target RAID for which the redundant level is to be adjusted. The techniques further involve: adjusting the redundant level of the target RAID from a first redundant level to a second redundant level. Such techniques can improve the performance of a RAID storage system.

Abstract: Aspects of this disclosure provide a technique for implementing polar encoding with incremental redundancy HARQ re-transmission. In particular, a transmitter encodes a message using different polar codes to obtain a first codeword and a second codeword that is twice the length of the first codeword, and transmit the first codeword as an original transmission, and the second half of the second codeword as a re-transmission without transmitting the first half of the second codeword. Information bits that are common to both the first codeword and the second half of the second codeword is mapped to more-reliable bit-locations in the second half of the second codeword. Decoded bit values for the common information in the original transmission and retransmission is compared by the receiver to perform a parity check.

Abstract: A method of managing data storage using a management device that includes determining respective status information for a plurality of storage devices, and calculating, based on the status information, a respective cost for each of the plurality of storage devices using a cost function that includes one or more parameters including at least one of: a program/erase (P/E) parameter, a block error state parameter, a block error level parameter, and a workload parameter. The method further includes selecting a destination storage device of the plurality of storage devices based on at least some of the calculated costs, and writing data to the destination storage device.

Abstract: A system and method of bootstrapping replicas from existing partitions is disclosed. A distributed database is maintained by a system. The distributed database includes a first partition copy and a second partition copy each containing a database. A failure of the first partition copy is detected and a third partition copy including an empty database is generated. The database of the second partition copy is copied to the empty database of the third partition copy and the third partition copy is designated as one of an active partition copy or a replica partition copy.

Abstract: A computer-implemented method according to one embodiment includes receiving, from an application at a metadata node of a clustered computing system, a request for a file, identifying, by the metadata node, a subset of data nodes within the clustered computing system where a portion of the file is stored, determining, by the metadata node, a data node within the subset of data nodes storing the portion of the file in a cache of the data node, and returning to the application, by the metadata node, a location of the portion of the file at the data node storing the portion of the file in the cache of the data node.

Abstract: Embodiments of the present disclosure relate to method, device and computer program product for managing Redundant Arrays of Independent Drives (RAID). The method comprises obtaining a log parameter associated with a status of a drive extent in the RAID from log pages of the RAID. The method also comprises determining, based on the log parameter, a prediction of a failure of the drive extent within a predetermined time interval. Moreover, the method further comprises in response to a determination that the drive extent is expected to fail, determining a reconstruction sequence of the RAID for a reconstruction of the RAID, such that the drive extent expected to fail within the predetermined time interval has a higher reconstruction priority than other drive extents in the RAID.

Abstract: A method for recovering data on a failed storage device includes detecting that a first storage device has a failure, creating a simulated management module where the simulated management module linked with a second storage device, writing a replica of at least some of the data as stored in the first storage device to a second storage device, creating a permanent management module and deleting the simulated management module.

Abstract: A computer-implemented method, according to one embodiment, includes: detecting an outage at a production site, and transferring I/O functionality to a first recovery site. In response to resolving the outage, first and second out-of-sync bitmaps are received from the first and second recovery sites, respectively. The out-of-sync bitmaps are merged together. Performance data which corresponds to achievable throughput is received from each of the first and second recovery sites, and the performance data is used to divide the merged out-of-sync bitmap into two portions. A request is sent to the first recovery site for data which corresponds to the first portion of the merged out-of-sync bitmap. Similarly, a request is sent to the second recovery site for data which corresponds to the second portion of the merged out-of-sync bitmap. Finally, data is received which corresponds to the first and second portions of the merged out-of-sync bitmap respectively, in parallel.

Abstract: Methods and systems for an enhanced restripe mechanism are provided. A system for an enhanced restriping mechanism includes a data storage module that stripes data across a plurality of storage devices, wherein the plurality of storage devices are arranged into a plurality of storage pools and the data is distributed across the plurality of storage pools. Also, the system may include a movement detection module that detects changes in the arrangement of the plurality of storage devices that would cause the data on a storage device in the plurality of storage devices to be moved onto other storage devices in the plurality of storage devices. Further, the system may include a restriping module that restripes disk data from the storage device in the plurality of storage devices onto the other storage devices in response to the detected change based on access characteristics of the data.

Abstract: Techniques are disclosed for decentralized data management using a geographic location-based consensus protocol in a network of computing resources such as, by way of example, a highly distributed system. For example, at a given consensus node of a consensus network comprising a plurality of consensus nodes configured to participate in a consensus protocol wherein at least a portion of the consensus nodes are mobile, a list is obtained of at least a subset of the plurality of consensus nodes that are predicted to be currently available to participate in the consensus protocol based on geographic location information. A message comprising a transaction to be validated is sent from the given consensus node to the subset of the plurality of consensus nodes in the obtained list. Techniques are also disclosed for adjusting a data protection policy based on the number of computing nodes, some of which are mobile, available to participate.

Abstract: An integrity processing unit includes rebuild modules to rebuild one or more encoded data slices in a dispersed storage network (DSN) memory unit. The rebuild modules determine a rebuild rate of the DSN memory unit, and, based on the rebuild rate, a rebuild rate status of the DSN memory unit. When the rebuild rate status is a high rebuild rate status, the rebuild rate to the DSN memory unit is reduced and, when the rebuild rate is not zero, the one or more encoded data slices are rebuilt in the DSN memory unit.

Abstract: A computing device includes an interface configured to interface and communicate with a dispersed storage network (DSN), a memory that stores operational instructions, and processing circuitry operably coupled to the interface and to the memory. The processing circuitry is configured to execute the operational instructions to perform various operations and functions. The computing device determine status of a set of memory devices of one or more sets of storage units (SUs) that distributedly store a set of encoded data slices (EDSs) within the DSN. The computing device detects one or more memory devices thereof that are failing and determines a number of available EDSs. When an insufficient number of EDSs are available, the computing device issues urgent read slice request(s) to recover additional available EDS(s) and facilitate temporary storage thereof within the DSN.

Abstract: Implementations of the present disclosure relate to a method, system and computer program product for managing a storage system. Specifically, in one implementation of the present disclosure there is provided a method for managing a storage system. The method comprises: dividing a source device among a plurality of storage devices in the storage system into a plurality of extents; copying data in the plurality of extents to a destination device; determining the state of an extent among the plurality of extents on the basis whether data in the extent among the plurality of extents has been copied to the destination device; and managing an access request to the extent on the basis of the state of the extent. In other implementations of the present disclosure, there is provided a corresponding system and computer program product.

Abstract: Aspects of this disclosure provide a technique for implementing polar encoding with incremental redundancy HARQ re-transmission. In particular, a transmitter encodes a message using different polar codes to obtain a first codeword and a second codeword that is twice the length of the first codeword, and transmit the first codeword as an original transmission, and the second half of the second codeword as a re-transmission without transmitting the first half of the second codeword. Information bits that are common to both the first codeword and the second half of the second codeword is mapped to more-reliable bit-locations in the second half of the second codeword. Decoded bit values for the common information in the original transmission and retransmission is compared by the receiver to perform a parity check.

Abstract: Implementing time-to-live (TTL) license management in an active/active (A/A) replication session is provided. In one aspect, a first host is assigned as a replication session manager, and is tasked with performing A/A replication management functions. The functions include granting a TTL license to a first and second storage array, providing IO requests to the arrays during a lifespan of the TTL license, and upon determining a communication failure occurred between the arrays, selecting one of the arrays as a winner and another as a loser; suspending the TTL license to the loser; and notifying the winner to suspend replication to the loser. Another aspect includes monitoring, by a second host, a communication connection between the first and second hosts. An aspect also includes upon determining the communication connection has failed between the first second hosts, reassigning the second host as the replication session manager to take over the management functions.

Abstract: Migrating servers from client networks to virtual machines (VMs) on a provider network. A migration appliance is installed or booted on the client network, and a migration initiator is instantiated on the provider network. A VM and associated volumes are instantiated on the provider network. The initiator sends a request for a boot sector to the appliance; the appliance reads the blocks from a volume on the client network, converts the blocks to a format used by the VM, and sends the blocks to the initiator. The initiator boots the VM using the boot sector and the VM begins execution. The initiator then retrieves all data blocks for the VM from volumes on the client network via the appliance, stores the data to the volumes on the provider network, and fulfills requests from the VM from either local volumes or the remote volumes via the appliance.

Abstract: Restoring a virtual machine is disclosed. An indication of the virtual machine of a primary site to be restored at a remote site using a copy stored at the remote site of a backup data of the virtual machine of the primary site is received. The virtual machine is restored to the remote site using a backup application deployed at the remote site as a virtual appliance managed using a virtual environment management platform.

Abstract: A method and system for managing a storage cluster is described. An identification of a plurality of nodes of a storage cluster to be removed from the storage cluster is received. It is determined whether to allow the removal of the plurality of nodes. In response to a determination that the removal of the plurality of nodes is allowed, identifications are made of data migrations to be performed to rebalance the data among nodes remaining in the storage cluster after removal of the plurality of nodes. The data migrations are performed. The plurality of nodes are removed from the storage cluster.

Abstract: Systems and methods for an incast mitigation approach that first modifies network responses for content requests above a threshold size to be delayed according a response latency selected from an established latency range. Additionally, as incast characteristics are analyzed from network traffic, the volumes can selectively modify the individual established latency range to increase the latency range during periods of higher incast characteristics and to decrease the latency range when incast characteristics appear to be decreasing.

Abstract: A control method and a control device are provided. A router receives data sent by a first device, where the data carries an identifier of an input/output (I/O) device, determines, according to the identifier of the I/O device and a correspondence between the I/O device and a controller, a controller corresponding to the identifier of the I/O device, sends the data to the controller corresponding to the identifier of the I/O device such that the controller processes the data according to firmware code stored in the controller, receives the processed data sent by the controller, and sends the processed data to a second device, where the second device or the first device is the I/O device. The firmware code is generally programmable, and therefore a control device applying the foregoing control method can be relatively flexibly implemented.

Abstract: The present invention may be a method, a system, and a computer program product. An embodiment of the present invention provides a method for ensuring anonymity of data. The method comprises the following: determining the number of members of each cluster, based on one or more features of leaving of the members of the data; and anonymizing the data in the database, using the determined number.

Abstract: Systems and methods are provided for testing a first computer device of a vehicle. A method includes selecting an operational component of the first computer device and selecting a test operation that is configured to utilize an entire capacity of the operational component. The method further includes instructing the first computer device to perform the test operation and to generate a first result. The method further yet includes retrieving a second result of the test operation and comparing the first result of the test operation from the first computer device with the second result. The method further yet includes indicating that the first computer device is faulty based at least in part on a difference between the first result and the second result.

Abstract: Techniques to protect data are disclosed. A backup appliance configuration data associated with a first backup appliance associated with a first virtual machine environment is received at a host site. The backup appliance configuration data is replicated to a remote replication site. The backup appliance configuration data includes data usable at the remote replication site to provide at the remote replication site a replicated backup appliance that is associated with a second virtual machine environment at the remote replication site and is configured to access backup data stored by the first backup appliance and to use said backup data stored by the first backup appliance to recover to hosts at the replication site one or more virtual machines associated with the first virtual machine environment.

Abstract: A distributed storage network (DSN) includes multiple distributed storage task execution (DST EX) units, each employing multiple memory portions to store encoded data slices. A DST EX unit detects a physical storage failure associated with an affected memory portion of a storage unit included in the DST EX unit. A memory portion identifier of the affected memory portion is used to identify a range of impacted encoded data slices associated with the affected memory portion, and in some cases specific encoded data slices within that range. The DST Ex unit issues rebuilding information to the DSN. The rebuilding information includes at least one identifier associated with at least one impacted encoded data slice included in the range of impacted encoded data slices.

Abstract: Examples disclosed herein relate to partial cache coherence. In some examples disclosed herein, a node connected to a memory fabric may include local cache connected to a local processor and a memory coherency proxy to. The memory coherency proxy may configure a portion of a fabric memory on the memory fabric as a proxy backing memory and expose the proxy backing memory to other nodes in the memory fabric as a fictitious local memory on the node, and may implement partial coherency for memory requests directed to the fictitious local memory. The fictitious local memory may have a memory address region different from a memory address region of a native local memory on the node.

Abstract: Disclosed herein are system, method, and computer program product embodiments for quorum-based replication of data records. In one embodiment, a read request for reading a record is received from a user node on a replica node of a cluster of replica nodes. The record is then determined not committed on the replica node. In response to the determination, an update message indicative of whether the number of replica nodes on which the record is durable exceeds a threshold is received on the replica node. In response to the number of replica nodes exceeds the threshold, a value of the record on the replica node is transmitted to the user node.