Abstract: A memory system includes a plurality of memory devices, a buffer memory, and a controller. The controller generates bitmap information for a plurality of pages to distinguish a first page on which a read operation has succeeded from a second page on which the read operation has failed, and stores the bitmap information in the buffer memory, whenever completing the read operation for each of the plurality of pages. The controller generates parity data by cumulatively performing a parity operation on data of the first page whenever performing the read operation on each of the plurality of pages, and stores the parity data in the buffer memory. The controller checks the bitmap information after the read operations on the plurality of pages are completed, and recovers data of the second page by referring to the parity data when the second page is present among the plurality of pages.

Abstract: A card engine may dynamically configure content for display via user equipment (UE). A rules engine may provide constructs to the card engine in the form of card definitions, which the card engine may evaluate using facts obtained from a facts controller. The card engine may create a hierarchy of containers, which are logical abstracts for containing cards. The containers in the hierarchy, which may be organized as a tree, may contain card definitions according to respective themes determined by the card engine. Variants may be assigned weights which can be changed dynamically based on factors such as user behavior, account condition, promotions or offerings. The card having the highest weight within its container is advanced up the tree. When a card reaches the top level of the tree, it may be formatted for display via the user interface and transmitted to the UE accordingly.

Abstract: A distributed storage system includes a first node group consisting of a plurality of nodes and a second node group consisting of a plurality of nodes. Each of the first node group and the second node group distributes and stores data of an assigned object to a plurality of constituent nodes. The first node group includes at least one first node shared with the second node group and at least one second node not shared with the second node group. The second node group includes the at least one first node and at least one third node not shared with the first node group.

Abstract: The present application discloses a task allocation method and task allocation apparatus for distributed data computing. The task allocation method includes: receiving storage parameters for target data to be computed in distributed data; mapping data slices of the target data to a resilient distributed dataset based on the storage parameters, each data slice corresponding respectively to a partition in the resilient distributed dataset; assigning each partition to a storage node to generate a computing task and perform the computing tasks. By using data storage information in a distributed database to allocate computing tasks to storage nodes corresponding to the data, Only data in local memories need to be called during the computing process, IO redundancy and time consumed due to repeated data forwarding are reduced.

Abstract: A method includes executing a set of read requests regarding a set of encoded data slices stored in storage units of a storage network, where a data segment is encoded in accordance with a dispersed storage error coding function to produce the set of encoded data slices, and where a decode threshold number of encoded data slices of the set of encoded data slices is needed to rebuild a missing or corrupt encoded data slice of the set of encoded data slices. The method further includes determining, for an encoded data slice, whether an integrity check value substantially matches a known integrity check value. When the integrity check value does not substantially match the known integrity check value, the method further rebuilding the encoded data slice based on the decode threshold number of encoded data slices and storing the rebuilt encoded data slice in the storage units.

Abstract: A simulation tool provides candidate volume mirror simulation in a data storage system. In one embodiment, user selections are received including a user selection of one or more candidate volumes of a primary data storage system for simulating mirroring to a secondary data storage system. As a function of received user selections, host-to-primary I/O activity to a candidate volume is simulated, recorded and measured over a selected interval of time. In addition, primary-to-secondary mirroring of a selected candidate volume to the secondary data storage system is simulated, recorded and measured over the interval of time. Performance measurements of the candidate volume mirror simulation are output by the simulation tool. Other features and aspects may be realized, depending upon the particular application.

Abstract: A system shares I/O load between controllers in a high availability system. For writes, a controller determines based on one or more factors which controller will flush batches of data from write-back cache to better distribute the I/O burden. The determination occurs after the local storage controller caches the data, mirrors it, and confirms write complete to the host. Once it is determined which storage controller will flush the cache, the flush occurs and the corresponding metadata at a second layer of indirection is updated by that determined storage controller (whether or not it is identified as the owner of the corresponding volume to the host, while the volume owner updates metadata at a first layer of indirection). For a host read, the controller that owns the volume accesses the metadata from whichever controller(s) flushed the data previously and reads the data, regardless of which controller had performed the flush.

Abstract: An apparatus comprises a host device configured to communicate over a network with source and target storage systems. The host device, in conjunction with migration of a logical storage device from the source storage system to the target storage system, is further configured to obtain from the target storage system watermark information characterizing progress of the migration of the logical storage device from the source storage system to the target storage system, and to determine whether a given input-output operation is to be sent to the source storage system or the target storage system based at least in part on the watermark information obtained from the target storage system. The watermark information illustratively identifies a particular logical address in the logical storage device, up to and including for which corresponding data has already been copied from the source storage system to the target storage system in conjunction with the migration.

Abstract: According to one general aspect, a system may include a data interface circuit configured to receive data access requests, wherein each data access request is associated with a data set. The system may include a plurality of storage devices each storage device configured to store data, and wherein the plurality of storage devices has an amount of available storage space, an amount of used storage space, and an amount of redundant storage space. The system may include a data management circuit configured to: monitor the amount of available storage space in the in the plurality of storage devices, determine, for one or more data set, a level of redundancy to be associated with the respective data set, generate, for a first data set of the data sets, a redundant data portion to be associated with the first data set, and dynamically adjust the level of redundancy associated with the first data set, based, at least in part, upon the amount of available storage space.

Abstract: Systems and methods for rebalancing storage-oriented workloads across resources of a distributed data storage facility. Communications are initiated between a client computing device and a plurality of storage target devices of a distributed storage system. The distributed storage system comprises one or more computing nodes that can host virtualized controllers. A client computing device interfaced with the distributed storage system uses an IP address to access an initial virtualized controller. Upon detecting a change event, conditions of the computing environment are analyzed to determine rebalancing options. Analysis of the rebalancing options results in identification of an alternative virtualized controller. A redirect message that identifies the alternative virtualized controller is sent to the computing device. The client computing device connects to the alternative virtualized controller.

Abstract: A data storage system includes multiple head nodes and data storage sleds. Volume data is replicated between a primary and one or more secondary head nodes for a volume partition and is further flushed to a set of mass storage devices of the data storage sleds. Volume metadata is maintained in a primary and one or more secondary head nodes for a volume partition and is updated in response to volume data being flushed to the data storage sleds. Also, the primary and secondary head nodes store check-points of volume metadata to the data storage sleds, wherein in response to a failure of a primary or secondary head node for a volume partition, a replacement secondary head node for the volume partition recreates a secondary replica for the volume partition based, at least in part, on a stored volume metadata checkpoint.

Abstract: Techniques manage a redundant array of independent disks. Such techniques involve: obtaining information on a wear level associated with each of a plurality of disks; selecting, based on the information on the wear level, a group of disks from the plurality of disks, a difference between the wear levels of any two of the group of disks being below a predetermined threshold; and creating a RAID with extents from the selected group of disks. Such techniques can sufficiently utilize the wear level to balance the data storage distribution among redundant arrays of independent disks, thereby enabling efficient management of redundant arrays of independent disks.

Abstract: A RAID storage multi-step command system includes a RAID storage system coupled to a RAID storage controller device. The RAID storage controller device identifies a RAID storage system configuration of the RAID storage system and, based on the RAID storage system configuration, generates a first multi-step command definition file for a first RAID storage device in the RAID storage system, and transmits it to the first RAID storage device. The first multi-step command definition file defines first steps that each include first operation(s). Subsequent to transmitting the first multi-step command definition file, the RAID storage controller device generates a first multi-step command that references the first multi-step command definition file and includes first parameter(s) for use in performing each first operation(s) included in the first steps defined by the first multi-step command definition file, and transmits the first multi-step command to the first RAID storage device.

Abstract: Techniques for storage management involve: acquiring capacities of a plurality of disks configured to provide redundant storage; determining, based on the capacities of the plurality of disks, a first total capacity corresponding to a first candidate scheme of the redundant storage and a second total capacity corresponding to a second candidate scheme of the redundant storage, all of the plurality of disks being used in the first candidate scheme, and a part of the plurality of disks being used in the second candidate scheme; and determining a target scheme of the redundant storage from the first candidate scheme and the second candidate scheme based on the first total capacity and the second total capacity. Accordingly, an optimal disk configuration scheme can be selected to generate an optimal disk group, so as to improve storage capability and storage management efficiency.

Abstract: Methods, systems, and devices for performing data migration operations using a memory system are described. The memory system may include a data migration component, such as a driver, for facilitating the transfer of data between a first memory device that may implement a first memory technology (e.g., having a relatively fast access speed) and a second memory device that may implement a second memory technology (e.g., having a relatively large capacity). The component may indicate the data migration operation to a second component (e.g., a controller) of the memory system. The second component may initiate the transfer of data between the first memory device and the second memory device based on the receiving the indication of the data migration operation. In some cases, the transfer of data between the first memory device and the second memory device may occur within the memory system without being transferred through a host device.

Abstract: Various embodiments generally relate to a semiconductor device, and more particularly, to a controller, a memory system and an operating method thereof. In an embodiment of the present disclosure, a controller for controlling a nonvolatile memory device may perform a sync-up operation of transmitting a logical-to-physical (L2P) map segment to a host to update the L2P map segment stored in a host memory included in the host when a map data changing event occurs, register the L2P map segment transmitted to the host and time information at which the sync-up operation is performed in a sync-up management list, calculate a sync-up period based on the time information, and perform the sync-up operation on an L2P map segment having a sync-up period greater than a threshold time, among L2P map segments registered in the sync-up management list.

Abstract: Embodiments of the present disclosure disclose a method, apparatus and system for controlling mounting of a file system. A specific embodiment of the method includes: receiving network attribute information of a target client sent by a target server as first network attribute information; determining, based on the first network attribute information, whether the target client has permission to mount to a target file system; and sending, in response to determining that the target client has permission to mount to the target file system, an identification of the target file system to the target server.

Abstract: Techniques for generating merge-friendly sequential IO patterns in shared logger page descriptor (PD) tiers. The techniques can be employed in an active-active clustered system that includes a primary storage node, a secondary storage node, a logger shared between the primary and secondary storage nodes, and a storage device such as a non-volatile memory (NVM) device. The techniques can include allocating at least a first trunk and a second trunk in a shared PD tier of the logger, sequentially writing PD metadata and/or data by the primary storage node and the secondary storage node to the first trunk and the second trunk, respectively, merging the PD metadata/data units sequentially written to each respective trunk together to obtain PD metadata/data having an increased size up to the size of the respective trunks, and storing the merged PD metadata/data to the NVM device.

Abstract: Techniques manage redundant arrays of independent drives (RAID). The techniques involve: in response to a target stripe to be built in the RAID, determining, from a resource pool, whether there are spare extents associated with at least one system disk. The techniques further involve: in response to determining that there are spare extents associated with at least one system disk, determining an adjacent relationship of used extents associated with the at least one system disk within a RAID stripe. The techniques further involve: determining, based on the adjacent relationship and the spare extents, an extent for building the target stripe. Accordingly, the total number of the RAID stripes including extents associated with the system disks can be reduced significantly, and a balance can be achieved within spare extents associated with system disks and spare extents associated with user disks for building a RAID stripe.

Abstract: Systems and methods for migrating stored backup data between disks (e.g., from an existing disk to another disk), such as a new or different disk in a magnetic storage library, without interrupting or otherwise affecting secondary copy operations (e.g., operations currently writing data to the storage library) utilizing the magnetic storage library, are described. In some embodiments, the systems and methods mark one or more mount paths as full when a running secondary copy operation associated with the mount path has completed a job (regardless of the actual current capacity or intended use of the mount path), and migrate each of the one or more data to a second disk of the data storage library when the mount path associated with the data is marked as full.

Abstract: A backup apparatus includes a hardware processor that selects one of a plurality of devices, the devices being communicably connected to each other and each including a storage apparatus and a connection I/F to connect to an external storage apparatus, and collectively makes a backup of backup target data held by the plurality of devices into the external storage apparatus connected to the connection I/F of a selected device, wherein the hardware processor selects one of the plurality of devices on a basis of a predetermined selection condition including an amount of data of backup target data held by each of the devices.

Abstract: A data set is constructed from a first given number of data elements configured from a plurality of data and redundant data corresponding to the plurality of data. The first given number of data elements are deployed in a distributed relationship into a first given number of first nodes. When an instruction to increase the number of data elements of the data set from the first given number by a second given number, the data set is reconstructed using, as new data elements, the first given number of data elements and a second given number of zero data. A controller deploys the data elements of the reconstructed data set in a distributed relationship into the first nodes and the second given number of second nodes while zero data or redundant data are deployed into the second nodes from among the data elements of the reconstructed data set.

Abstract: Disclosed herein are system, method, and computer-program product embodiments for generating a paged and in-memory representation of a database object. An embodiment operates by maintaining in-memory and paged form primitives unique to the database object or a substructure thereof in a database such that the in-memory and paged form primitives are capable of providing the in-memory and paged representations of the database objects, respectively. Thereafter, a load configuration for the database object is determined. Based on the load configuration, the in-memory and/or paged representations of the database object are generated using the in-memory form primitive or the paged form primitive unique to the database object, respectively. Subsequently, the in-memory and/or paged representations of the database object are stored in the database.

Abstract: Techniques for providing an efficient virtualization layer structure in a data storage system. The techniques include implementing multiple layers of indirection for accessing host data in the data storage system, including a mapping layer, a virtualization layer, and a physical layer. The virtualization layer includes virtual layer blocks (VLBs), each VLB including virtual pointers. Each virtual pointer is pointed to by one or more leaf pointers in the mapping layer, and points to a data block in the physical layer. The techniques include generating, for each virtual pointer in the VLB, reference count metadata to keep track of the number of leaf pointers pointing to the virtual pointer, and maintaining, in a metadata page, the reference count metadata for the virtual pointers in a three (3)-way mirror. The techniques include maintaining each VLB of the virtualization layer in a RAID stripe across multiple physical drives in the data storage system.

Abstract: Techniques for splitting a disk set involve obtaining stripe shared information in a first disk set, wherein the information indicates a stripe set that shares a plurality of disks. The techniques further involve determining the number of disks to be split from the first disk set. The techniques further involve splitting the first disk set into a first portion and a second portion based on the information and the number of disks to be split, wherein the second portion and one or more newly added disks form a second disk set, and both the first disk set and the second disk set store data through Redundant Array of Independent Disks (RAID). In the case that a current disk set needs to be split due to adding one or more new disks, disks are selected using the collected information, thereby reducing data movements caused by splitting of the disk set.

Abstract: Provided is a storage system and a storage management method, aiming at reducing data movement amount necessary for using an expanded capacity in a distributed RAID. When only A (A is a positive integer) physical storage drives are added, a storage controller selects virtual parcels that are mapped to different physical storage drives among N physical storage drives and are included in different virtual chunks, changes an arrangement of the selected virtual parcels to the added A physical storage drives, and constitutes a new chunk based on unallocated virtual parcels selected from different physical storage drives among the (N+A) physical storage drives.

Abstract: Embodiments of the present disclosure provide a method, apparatus and computer readable medium for managing a plurality of disks. The method includes in response to receiving a write request for a first stripe of a redundant array of independent disks (RAID), searching for extents mapped to the first stripe. The RAID is created on a plurality of extents obtained by dividing a plurality of disks. The method further includes, in response to the extents mapped to the first stripe being missed, selecting a first set of extents in a free state from the plurality of extents of the plurality of disks. The method further includes mapping the first stripe to the first set of extents.

Abstract: Sector signature patterns with sector signature values and sector signature parity values are embedded with data slices. A new pattern is embedded with a slice each time the slice data is updated. The patterns are selected in order such that every sector signature value and sector signature parity value changes when a new pattern is embedded. A separate metadata record such as a key is maintained to indicate which pattern has been embedded with the slice. A data integrity check is performed by comparing the embedded sector signature parity values with the metadata record and/or performing a pattern-to-key lookup.

Abstract: In a data access method, after an interface card receives a first data write instruction or a first data read instruction, the interface card generates a second data write instruction or a second data read instruction, and writes the second data write instruction or the second data read instruction into a cache. No resource of a processor of a storage device is used. After the interface card writes the second data write instruction or the second data read instruction into the cache, a cache control unit sends the second data write instruction or the second data read instruction to a storage subsystem. No resource of the processor of the storage device is used. Alternatively, the cache control unit may instruct the storage subsystem to execute the second data write instruction or the second data read instruction.

Abstract: Disclosed are devices, method and/or systems for responding to a request for accessing a portion of a memory prior to completion of a requested operation to place the portion of the memory in an initialized state. In one example implementation, a memory controller may delay initiation of a write operation addressed to a particular portion of the memory until completion of a pending request to initialize the particular portion of the memory. In another example implementation, a memory controller may return values to service a request for a read operation comprising values representing an initialized state without accessing the particular portion of the memory responsive to a presence of a pending request to initialize the particular portion of the memory.

Abstract: A method of operating a plurality of blades of a storage system, performed by the storage system, is provided. The method includes writing data stripes across one or more sets of blades of the plurality of blades within resiliency groups, the plurality of blades having computing resources and storage memory, each resiliency group supporting data recovery in case of loss of a specified number of blades of the resiliency group. The method includes transferring data from a first resiliency group to a second resiliency group, responsive to a change in geometry of the storage system.

Abstract: A method, computer program product, and computing system for receiving a request to reconfigure a data array that currently includes N data drives and P parity drives to include N data drives and P+1 parity drives; confirming the availability of the P+1 parity drive; and distributing a plurality of new parity portions across the N data drives and P+1 parity drives.

Abstract: Techniques are provided for synchronous replication for synchronous mirror copy guarantee. A file system dependent technique for synchronous mirror copy guarantee is provided by overriding default behavior of a persistent fence so that the persistent fence is activated to block operations targeting a storage object having a synchronous replication relationship based upon the synchronous replication relationship being out of sync. The default behavior of the persistent fence is overridden to allow operations to be executed upon the storage object based upon the synchronous replication relationship being in sync. A file system independent technique for synchronous mirror copy guarantee is provided by intercepting operations before the operations are received by a file system. The operations are selectively forwarded to the file system or not based upon a state of a synchronous replication relationship.

Abstract: In one embodiment, an apparatus includes a host controller to couple to an interconnect to which a plurality of devices may be coupled. The host controller may include: a first driver to drive first information onto a first line of the interconnect; a second driver to drive a clock signal onto a second line of the interconnect; and a mode control circuit to cause the second driver to drive the clock signal onto the second line of the interconnect in a first mode and to cause the first driver and the second driver to drive differential information onto the first line and the second line of the interconnect in a second mode. Other embodiments are described and claimed.

Abstract: A data recovery method for a Redundant Array of Independent Disks (RAID) system is provided. The RAID system includes a plurality of drives and a processor. Each drive includes a plurality of data pages. The drives form a plurality of data strips over the drives through stripping processing. Each data strip includes one of the data pages of every drive. The processor writes data to the data strips in a log-based manner and records whether each data page of each data strip is valid or invalid. During recovery of data from a broken one of the drives, data is recovered from a corresponding valid or written data page but is not recovered from a corresponding invalid or blank data page.

Abstract: Backup of application data associated with an application executing in a virtual machine managed by a hypervisor is performed. Backup of the application data includes retrieving a Logical Unit Number (LUN) identification (ID) used by the application to store the application data in a storage volume. Backup of the application data also includes performing a virtual storage resolution for the LUN ID to determine whether the application data is stored in the storage volume identified by the LUN ID based on a first virtual mapping or a physical mapping. Backup also includes storing in metadata for the backup the LUN ID and whether the LUN ID is based on the first virtual mapping or the physical mapping. Backup includes creating a backup of the application data stored in the storage volume. Application data can subsequently be restored based on the application data that is backed up.

Abstract: Embodiments of the present disclosure disclose a data processing method, including: receiving an upload instruction for a target file; obtaining storage location information of the target file in response to the upload instruction; and uploading the target file to a corresponding target first storage device in K first storage devices and M second storage devices according to location information of the K first storage devices and location information of the M second storage devices, so that when determining that a preset condition is satisfied, a target second storage device in the M second storage devices generates M parity blocks according to a file stored in the target second storage device, respectively stores M?1 parity blocks in remaining M?1 second storage devices, deletes the file stored in the target second storage device, and instructs the remaining M?1 second storage devices to delete files stored in the remaining M?1 second storage devices.

Abstract: Methods, apparatus, systems and articles of manufacture to facilitate atomic compare and swap in cache for a coherent level 1 data cache system are disclosed. An example system includes a cache storage; a cache controller coupled to the cache storage wherein the cache controller is operable to: receive a memory operation that specifies a key, a memory address, and a first set of data; retrieve a second set of data corresponding to the memory address; compare the second set of data to the key; based on the second set of data corresponding to the key, cause the first set of data to be stored at the memory address; and based on the second set of data not corresponding to the key, complete the memory operation without causing the first set of data to be stored at the memory address.

Abstract: Approaches for routing data to storage are provided. An approach includes determining implicit metadata from explicit metadata received with a request from a user to store a file. The approach also includes determining a storage resource based on the explicit metadata, the implicit metadata, and a registry of storage resources. The approach additionally includes routing data of the file to the determined storage resource.

Abstract: Provided are an electronic system for adaptively adjusting allocation of a memory area and a method of operating the electronic system. The electronic system includes: a modem configured to perform data transmission; at least one IP block configured to execute an application; a boot data memory configured to store first boot data corresponding to the alternative mode and second boot data corresponding to a standard mode; a main memory including a first area allocated to the modem and a second area allocated to the at least one IP block, in the standard mode; and a processor configured to boot the main memory by using the first boot data or the second boot data based on an operation mode, wherein the processor is configured to re-allocate the first area to the at least one IP block by re-booting the main memory by using the first boot data in the alternative mode.

Abstract: Provided are a computer program product, system, and method for using a machine learning module to determine when to perform a data integrity check of copies of a data set. Input on storage attributes of a plurality of storage units, each storage unit of the storage units storing a copy of a data set, is provided to a machine learning module to produce an output value. A determination is made as to whether the output value indicates to perform a data integrity check of the copies of the data set. A determination is made as to whether the copies of the data set on different storage units are inconsistent in response to determining to perform the data integrity check. At least one of the copies of the data set is corrected to synchronize all the copies of the data set.

Abstract: Techniques manage a storage system. The techniques involve: in response to a first control unit of the storage system receiving an access request to a target storage area in the storage system, determining whether the target storage area is located in a first storage area or a second storage area; in response to the target storage area being located in the second set of storage areas, determining that a second control unit of the storage system processes the access request, the first control unit and the second control unit sharing the storage system; and updating an access state of the first control unit to the target storage area, the access state indicating access permission for the target storage area included in the first control unit. Such techniques can effectively reduce the number of CMI messages related to a stripe lock mechanism in a dual active SP.

Abstract: A computer-implemented method according to one embodiment includes identifying an erasure code storage policy for an unified file and object storage system, determining a plurality of storage disks associated with the erasure code storage policy, retrieving disk health parameters for each of the plurality of storage disks, identifying a number of available outer partition storage blocks for each of the plurality of storage disks, and determining a number of erasure code fragments to be stored for a file within the unified file and object storage system before initiating an objectization process on the file, utilizing the disk health parameters for each of the plurality of storage disks and the number of available outer partition storage blocks for each of the plurality of storage disks.

Abstract: Systems and methods for mapping random data writes to sequential or semi-sequential storage. Data writes may be initially directed to an SSD or other relatively low latency and high IOPS data storage layer. The data may remain in the SSD storage layer until a group of data may be written, together, to a sequential or semi-sequential storage layer. A data organizer may group the data into data buckets based on tags and/or policies associated with the data. In this way, data subject to similar lifetime, priority, data protection, and/or other policies may be stored on a same segment or other portion of the sequential storage layer. Similarly, data having similar access patterns, authors, files, objects, or project affiliations, may be stored together on a same segment of the sequential storage layer.

Abstract: A storage apparatus includes a non-volatile storage device configured to store data; a memory; and a processor coupled to the memory and configured to control access to the non-volatile storage device, the processor configured to: receive an instruction from external software as a task, generate a command set for controlling the non-volatile storage device, execute a command included in the generated command set, control firmware revision processing of the storage apparatus, and stop execution of the command after performing processing for suppressing abnormality detection of the external software at a timing at which the command is not executable during the firmware revision processing.

Abstract: A storage unit (SU) 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 SU, of a first SU set, receives a partially encoded slice request to restore a set of encoded data slices (EDSs) that are based on first dispersed storage error coding function parameters. The SU generates a decode threshold number of partially EDSs based on the first and second dispersed storage error coding function parameters. The SU then outputs the decode threshold number of partially EDSs to a second SU set to undergo selective combination respectively to generate new EDSs for storage within the SUs of the second decode threshold number of SUs of the second SU set.

Abstract: A system hosts a file system representing a replica of file systems hosted on a plurality of nodes, each node storing data on a first storage medium. The system stores data on a second storage medium that is slower than the first storage medium. The system stores on the second storage medium a file received from one of the nodes when the file remains un-accessed by the nodes for a predetermined period of time. The first storage medium on the plurality of nodes stores a pointer to the file and not the data content of the file stored on the second storage medium. The system provides the file from the second storage medium to the first storage medium on one of the nodes while providing the plurality of nodes read and write access to the file stored on the second storage medium using the pointer on the first storage medium.

Abstract: Storage management techniques involve determining a set of association degrees associated with a set of storage disks, the set of storage disks forming a set of Redundant Arrays of Independent Disks (RAIDs), and an association degree of the set of association degrees indicating a coupling degree of a pair of storage disks in the set of storage disks, the coupling degree being determined based on a number of RAIDs associated with the pair of storage disks. Such techniques further involve determining a first number of pairs of storage disks, wherein the coupling degree of each pair of storage disks is less than a predetermined coupling threshold; and in response to determining that a ratio of the first number to a total number of pairs of storage disks of the set of storage disks is greater than a predetermined ratio threshold, reorganizing at least one RAID in the set of RAIDs.

Abstract: The various embodiments relate to a storage system, storage system method and computer program product including: providing a distributed collection of drives, each drive having logical blocks, each logical block being assignable to a segment with an associated volume and being configurable to RAID characteristics associated with that volume; assigning a first group of logical blocks to a segment with an associated volume and configuring the first group of logical blocks to RAID characteristics associated with that volume; and wherein a further group of logical blocks is ready to be assigned to any segment but is not yet assigned.

Abstract: One example method includes receiving an IO request that specifies an operation to be performed concerning a data block, determining if a policy exists for a device that made the IO request, when a policy is determined to exist for the device, comparing the IO request to the policy, recording the IO request, and passing the IO request to a disk driver regardless of whether the IO request is determined to violate the policy or not.