Abstract: A method begins by a processing module determining whether a memory device of a dispersed storage (DS) unit is unavailable to produce an unavailable memory device. The method continues with the processing module determining a methodology regarding DS encoded data stored in the unavailable memory device based on one or more dispersed storage network (DSN) conditions to produce a determined methodology when the memory device is unavailable. The method continues with the processing module initiating, in accordance with the determined methodology, a rebuilding function to rebuild the DS encoded data to produce rebuilt DS encoded data when the determined methodology includes a rebuilding component. The method continues with the processing module storing the rebuilt DS encoded data within available memory of the DS unit.

Abstract: Techniques are described for processing a data operation that writes first data to a data portion currently stored on first physical storage of a first storage tier of a data storage system, including storage tiers each having a different performance ranking relative to other storage tiers. Second physical storage is allocated from one of the storage tiers for storing the first data written to the data portion. This one storage tier is selected independent of the first storage tier. The first data is stored in a cache and destaged from the cache to the second physical storage. A single merged copy of data for the data portion is formed. Based on an activity level of the data portion, a target tier is selected for storing the single merged copy of data for the data portion.

Abstract: Described are techniques for enforcing an allocation policy. Information is received that describes one or more storage groups. Each of the storage groups includes one or more thin devices. Each of the thin devices includes a plurality of chunks of storage allocated on one or more of a plurality of storage tiers. For each of the one or more storage groups, a plurality of counters is determined indicating amounts of storage currently allocated from the plurality of storage tiers for use by the storage group. Using the plurality of counters, it is determined whether each of the one or more storage groups violates thresholds included in an allocation policy associated with each storage group. Each of the thresholds specifies a maximum amount of storage of one of the plurality of storage tiers that can be used by each storage group.

Abstract: Various embodiments for improving data storage and retrieval performance, for a tiered storage environment having levels corresponding to storage performance, are provided. In one embodiment, by way of example only, reference count information of at least one data segment maintained in the tiered storage environment is used to determine which of the levels in the tiered storage environment the at least one data segment will be assigned. Those of the at least one data segment having higher reference counts are assigned to a higher performance level than those having lower reference counts.

Abstract: An abstraction for storage class memory is provided that hides the details of the implementation of storage class memory from a program, and provides a standard channel programming interface for performing certain actions, such as controlling movement of data between main storage and storage class memory or managing storage class memory.

Abstract: An abstraction for storage class memory is provided that hides the details of the implementation of storage class memory from a program, and provides a standard channel programming interface for performing certain actions, such as controlling movement of data between main storage and storage class memory or managing storage class memory.

Abstract: A method and system is disclosed that remaps logical block addresses (LBAs) for defragmentation that is managed at the storage device level. The remapping may include sequentially remapping LBAs where individual files are remapped so that each file is referenced by sequential LBAs. The remapping of LBAs may be performed without changes to the physical location of data.

Abstract: In a flash memory device, after an updated value is copied from a first block to a second block, a block management value of the first block is set to an unused state, and maintenance is performed to erase data from the first block. When performing maintenance, the block management value of the first block B1 is rewritten from “$FFF0” to “$FFFF.” When a reset occurs and the power supply is deactivated during the maintenance, the digit of “$0” in the block management value may become “1” to “E” of the hexadecimal system. In this manner, when the block management value includes a single digit of “1” to “E” and three digits of “F,” the reading of an updated value from the block corresponding to the block management value is restricted.

Abstract: A memory system is provided. The system includes a controller that regulates read and write access to one or more FLASH memory devices that are employed for random access memory applications. A buffer component operates in conjunction with the controller to regulate read and write access to the one or more FLASH devices. Wear leveling components along with read and write processing components are provided to facilitate efficient operations of the FLASH memory devices.

Abstract: A computer of a data storage system carries out user input-output requests for data of a set of virtual disks by performing back-end input-output requests to a set of overprovisioned storage devices providing underlying physical storage. A set of time series of utilization measures are continually generated and stored, with each reflecting an amount of a given virtual disk consumed by user data at a given time. The time series are used to generate predicted utilization measures, each being an estimate of an amount of a given virtual disk expected to be consumed by user data at a future time. A fullness probability measure is generated by aggregating the predicted utilization measures, and it reflects a probability that the set of overprovisioned storage devices will be fully consumed by user data at the future time.

Abstract: Technique for decision criterion for determining a transfer destination layer in rearrangement processing. A computer configures rearrangement reference information showing whether an access characteristic related to a task executed on a plurality of host computing devices is considered as a decision criterion for transfer destination determination in rearrangement processing of transferring data between actual storage areas of physical storage devices of different response performance. Storage subsystem refers to the rearrangement reference information and, based on an access characteristic of the plurality of computing devices with respect to the actual storage areas assigned to the plurality of computing devices, executes rearrangement processing of transferring data stored in the actual storage areas to different actual storage areas in the physical storage devices of different response performance.

Abstract: An embodiment of this invention is a storage management system including a processor and a storage device to manage a storage system having one or more copy functions. The processor locates data designated to determine a backup method. The storage device stores copy function management information on the one or more copy functions of the storage system. The processor refers to the copy function management information to ascertain the unit of copy operation of each of the one or more copy functions. The processor determines a candidate for a copy function of the storage system to be used to back up the designated data depending on the data configuration in a volume holding the designated data and the unit of copy operation of the candidate for the copy function.

Abstract: An autonomous sub-system receives a database downloaded from a host controller. A controller monitors bus traffic and/or allocated resources in the subsystem and re-allocates resources based on the monitored results to dynamically improve system performance.

Abstract: A memory scanning system may scan memory objects to determine usage frequency by scanning each memory object using a mapping of the processes stored in memory. The scanning may be performed multiple times to generate a usage history for each page or unit of memory. In some cases, scanning may be performed at different frequencies to determine multiple classifications of usage. The mapping may create a detailed topology of memory usage, including multiple classifications of access frequency, as well as several other classifications. Based on the topology, the objects in memory may be copied to another storage medium or optimized for performance or power consumption.

Abstract: Embodiments relate to a system and computer program product for data management. An aspect includes a method for assigning storage types to data based on access frequency. Past or historical data associated with current data usage is also considered prior to assignment. Once data frequency access is determined, the current data is assigned to a first tier of a plurality of hierarchical ordered tiers, each tier corresponding to at least one class of storage. In one embodiment, there may be a condition that overrides the assignment with option to override it. The tier assignment may also be preserved so that the current data can be appropriately assigned in the future.

Abstract: A method of operating a memory system is provided. The method includes a controller that regulates read and write access to one or more FLASH memory devices that are employed for random access memory applications. A buffer component operates in conjunction with the controller to regulate read and write access to the one or more FLASH devices. Wear leveling components along with read and write processing components are provided to facilitate efficient operations of the FLASH memory devices.

Abstract: An apparatus and method for managing data in hybrid memory are disclosed. The apparatus for managing data in hybrid memory may include a page access prediction unit, a candidate page classification unit, and a page placement determination unit. The page access prediction unit predicts an access frequency value for each page for a specific period in a future based on an access frequency history generated for the page. The candidate page classification unit classifies the page as a candidate page for migration based on the predicted access frequency value for the page. The page placement determination unit determines a placement option for the classified candidate page.

Abstract: Systems and computer program products are provided for optimizing selection of files for deletion from one or more data storage devices to free up a predetermined amount of space in the one or more data storage devices. A method includes analyzing an effective space occupied by each file of a plurality of files in the one or more data storage devices, identifying, from the plurality of files, one or more data blocks making up a file to free up the predetermined amount of space based on the analysis of the effective space of each file of the plurality of files, selecting one or more of the plurality of files as one or more candidate files for deletion, based on the identified one or more data blocks, and deleting the one or more candidate files for deletion from the one or more data storage devices.

Abstract: Systems and computer program products are provided for optimizing selection of files for eviction from a first storage pool to free up a predetermined amount of space in the first storage pool. A method includes analyzing an effective space occupied by each file of a plurality of files in the first storage pool, identifying, from the plurality of files, one or more data blocks making up a file to free up the predetermined amount of space based on the analysis of the effective space of each file of the plurality of files, selecting one or more of the plurality of files as one or more candidate files for eviction, based on the identified one or more data blocks, and evicting the one or more candidate files for eviction from the first storage pool to a second storage pool.

Abstract: In accordance with the present disclosure, a system and method for performing a system memory save in tiered or cached storage during transition to a decreased power state is disclosed. As disclosed herein, the system incorporating aspects of the present invention may include a flash or other nonvolatile memory such as a solid-state drive, volatile memory, and at least one alternate storage media. Upon transition to a decreased power state, at least some of the data in the solid-state drive, for example, may be transferred to the at least one alternate storage media. After the SSD data is transferred, data stored in volatile system memory, such as a system context, may be transferred to the SSD memory. With the system context saved in SSD memory, power to the volatile system memory may be turned off.

Abstract: Disclosed are an apparatus and method for recycling areas of a data storage device by relocating data. In one embodiment, a method may comprise selecting a first storage area based on a quantity of obsolete data in the first storage area, moving valid data from the first storage area to a second storage area, and setting memory spaces corresponding to the first storage area as available memory for storing other data. Another embodiment may further comprise selecting a physical address-based move operation or a logical address-based move operation based on a number of sets of contiguous valid memory spaces in the first storage area, wherein the physical address-based move comprises moving data based on physical data addresses, and logical address-based moved comprises moving data based on logical block addresses.

Abstract: A storage control apparatus forms a RAID by plural storage media and stores and holds data on a file-by-file basis. A number-of-writable-times management unit manages the number of writable times for each storage medium. A write-destination management unit manages data write destinations in the storage media. When updating write object data whose write destination is one of storage media constituting a group (first storage medium), a relocation unit relocates the write object data by setting a write destination to a second storage medium which is different from the first storage medium. A write-destination update unit updates the data write destinations in the storage media managed by the write-destination management unit according to the relocating. Through the relocating, the storage control apparatus is able to control the number of writable times which decreases along with data writing.

Abstract: An example of an information storage system includes physical storage drives for providing real storage areas to a pool which is tiered into tiers different in performance, and a controller. The controller monitors accesses in a first tier in the pool. The controller determines a loaded state of the first tier based on the accesses to the first tier. The controller holds management information relating loads to the first tier to relocation speeds and/or modes of moving data in data relocation between a second tier in the pool and the first tier. The controller determines at least one of a relocation speed and a mode of moving data in data relocation between the second tier and the first tier based on the determined loaded state of the first tier and the management information.

Abstract: A computer-implemented method for recovering virtual machines after disaster scenarios may include (1) identifying a request to restore a virtual machine disk backup image to a virtual machine disk, (2) in response to the request, identifying a block map of the virtual machine disk backup image, the block map identifying at least one allocated block as allocated on the virtual machine disk and at least one unused block as unused on the virtual machine disk, and then (3) restoring the allocated block from the virtual machine disk backup image to the virtual machine disk upon determining that the block map identifies the allocated block as allocated, but skipping restoration of the unused block from the virtual machine disk backup image to the virtual machine disk due to determining that the block map identifies the unused block as unused. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: Methods, systems, and computer program products are provided for optimizing selection of files for eviction from a first storage pool to free up a predetermined amount of space in the first storage pool. A method includes analyzing an effective space occupied by each file of a plurality of files in the first storage pool, identifying, from the plurality of files, one or more data blocks making up a file to free up the predetermined amount of space based on the analysis of the effective space of each file of the plurality of files, selecting one or more of the plurality of files as one or more candidate files for eviction, based on the identified one or more data blocks, and evicting the one or more candidate files for eviction from the first storage pool to a second storage pool.

Abstract: Transparent file system migration including a method that identifies a source physical storage location in a file system that supports simultaneous access by multiple independent processes. A target physical storage location in the file system is identified and its contents are migrated to the target physical storage location. The migrating includes disallowing new allocations to the source physical storage location and copying contents from the source physical storage location to the target physical storage location. A write request to write data to the source physical storage location is received prior to or during the migrating. The write request is serviced contemporaneously with the migrating. Read and write requests directed to the source physical storage location are redirected to the target physical storage location. The redirecting is responsive to the migrating completing. The requests are from the multiple independent processes and include both logical and physical input/outputs.

Abstract: Methods, systems, and computer program products are provided for optimizing selection of files for deletion from one or more data storage devices to free up a predetermined amount of space in the one or more data storage devices. A method includes analyzing an effective space occupied by each file of a plurality of files in the one or more data storage devices, identifying, from the plurality of files, one or more data blocks making up a file to free up the predetermined amount of space based on the analysis of the effective space of each file of the plurality of files, selecting one or more of the plurality of files as one or more candidate files for deletion, based on the identified one or more data blocks, and deleting the one or more candidate files for deletion from the one or more data storage devices.

Abstract: Each node in a clustered array is the owner of a set of zero logical disks (LDs). Thinly-provisioned VVs (TPVVs) are partitioned so each is mapped to a group of zero LDs from different sets of zero LDs. When there is a change in ownership, the affected zero LDs are switched one at a time so only a group of the TPVVs is affected each time.

Abstract: Various embodiments for improving data storage and retrieval performance, for a tiered storage environment having levels corresponding to storage performance, are provided. In one embodiment, by way of example only, reference count information of at least one data segment maintained in the tiered storage environment is used to determine which of the levels in the tiered storage environment the at least one data segment will be assigned. Those of the at least one data segment having higher reference counts are assigned to a higher performance level than those having lower reference counts.

Abstract: In one embodiment an controller comprises logic, at least partially including hardware logic, configured to logic, at least partially including hardware logic, configured to receive location data from a location measurement apparatus, buffer the location data in a local memory, and release the location data from the local memory to a remote processor in response to one or more trigger conditions. Other embodiments may be described.

Abstract: An apparatus for managing a memory including a working region and a compression region is provided. The working region stores uncompressed data. The apparatus includes a management module and a compression/decompression module. According to a recent used index and a compression ratio of a set of target data stored in the working region, the management module determines whether to transfer the target data to the compression region. When the management module determines to transfer the target data to the compression region, the compression/decompression module compresses the target data and transfers the compressed target data to the compression region.

Abstract: In an example, an analytic function to be performed on data stored in an input block is managed through an interface to a framework through which a user is to define the analytic function. The framework is to buffer batches of the data into a memory through implementation of a Reader, a Writer, a PreReader, and a PreWriter on the data stored in the input block when the user-defined analytic function is performed, and wherein the Reader, the Writer, the PreReader, and the PreWriter are individually movable with respect to each other in the input block. In addition, the user-defined analytic function is received through the interface.

Abstract: A method for managing a memory pool in a memory heap partitioned into consecutive memory segments includes deleting a specific memory segment by: receiving an identification key for the specific memory segment, determining a start address and a size of the specific memory segment from a translation table based on the identification key, and moving memory segments, which are allocated behind the start address of the specific memory segment in the memory heap, towards the beginning of the memory heap by the size of the specific memory segment, such that the memory pool consists of a first section, which is continuously allocated, and a second section, which is continuously unallocated.

Abstract: Methods, systems, and computer readable media for partition and cache restore are disclosed. According to one aspect, a method for partition and cache restore includes, in a computing platform having a mass storage device and a non-volatile cache storage device that operates as a cache for the mass storage device: providing, in a first location within the mass storage device, a first image of data; providing, in a second location within the mass storage device, a second image of data; copying the first image of data from the first location within the mass storage device to a third location within the mass storage device; and copying the second image of data from the second location within the mass storage device into the non-volatile cache storage device.

Abstract: Responsive to an instruction to collapse a derivative version of an ancestor data volume into the ancestor data volume, it is determined if a characteristic of the derivative version of the ancestor data volume satisfies a criteria relative to a characteristic of the ancestor data volume. If the characteristic of the derivative version satisfies the criteria, the ancestor data volume is merged into the derivative version of the underlying data to form an updated derivative version. The updated derivative version is established as the ancestor data volume.

Abstract: A computer implemented method, system, and program product for data consistency comprising establishing a memory-mapped file, enabling the memory-mapped file data to be paged to the non-volatile storage medium, receiving, at a consistency layer, a write IO; wherein the write IO corresponds to a space on the storage medium, issuing a read IO to the storage medium, wherein the read IO corresponds to the space on the storage medium to be overwritten by the write IO, writing the data of the read IO to a undo log and writing the write IO to the storage medium.

Abstract: A method of managing a memory in a computer system including a processor executing programs and the memory, the memory including a first area, which is managed by a garbage collector, and a second area, which is not managed by the garbage collector, the method including the steps executed by the processor of: checking a reference relation of basic point data associated with the second area by tracing references from the basic point data; when the reference relation of the basic point data has a structure including a reference to data belonging to the same class as the class of the basic point data, determining that particular data out of data constituting the structure is prohibited from being migrated to the second area; and migrating data stored in the first area out of data remaining after excluding the particular data from the data constituting the structure to the second area.

Abstract: Activity level of memory pages is classified in virtual machine environment, so that processes such as live VM migration and checkpointing, among others, can be carried out more efficiently. Because each such hypervisor-based service may desire classification of activity levels of memory pages at different frequencies and different time granularities, the hypervisor supports methods to classify activity levels of memory pages for a plurality of time intervals.

Abstract: A system is disclosed that includes a content addressable memory and an input register coupled to the content addressable memory. The input register can store a data word and the content addressable memory determines if the data word exists in the content addressable memory. The system also includes a power control circuit coupled to the content addressable memory for selectively providing power to at least a portion of the content addressable memory. The system includes power control logic coupled to the power control circuit to selectively reduce power to the at least a portion of the content addressable memory when valid data does not exist in the at least a portion of the content addressable memory.

Abstract: A second storage maps a migration source volume to a virtual volume of a migration destination volume according to storage virtualization technology. A host system including a host switches an access path from an access path to the migration source volume to an access path to the migration destination volume. The second storage executes copy processing of migrating, from the migration source volume to the migration destination volume, data in an assigned area of a virtual volume according to thin provisioning of the migration source volume based on the information contained in the first thin provisioning information in the first storage, and copying that data from the migration destination volume to a virtual volume according to thin provisioning of a copy destination volume in the second storage. The second storage associates the virtual volume of the copy destination volume with the migration destination volume in substitute for the original virtual volume.

Abstract: A method of providing a relevant subset of information to a client device is based in part on scanning for Wi-Fi access points within range of the client device, using a Wi-Fi database that covers a large target region to retrieve information about these access points, using this information to estimate the position of the mobile client device, selecting a limited region in the vicinity of the estimated location of the client device, and providing information about Wi-Fi access points within this limited region to the client. For efficient transfer and maintenance of data, the target region may be divided into a hierarchy of fixed geographical tiles.

Abstract: The present invention is directed to a method and software for managing the host-to-volume mappings of a SAN storage system. The host-to-volume mappings of the SAN storage system are represented in mapping configuration components. The active mapping configuration component represents the current host-to-volume mapping for the SAN storage system. Only one mapping configuration component is active at a time. The host-to-volume mappings of the SAN storage system are changed by deactivating the active mapping configuration component and activating an inactive mapping configuration component that represents a different mapping configuration, effecting a repartition, repurpose, disaster recovery, or other business activity. This can be a scheduled task or performed in an on-demand manner. The mapping configuration components are managed and controlled through the management component of the SAN storage system.

Abstract: A data storage subsystem is disclosed that implements a process for storing and/or reconstructing system data, such as a system mapping table. In certain embodiments, table pages and log pages are systematically copied, or flushed, to non-volatile memory in an interleaving manner according to a fixed ratio of log pages to table pages, thereby facilitating coherency of data. Full and/or partial reconstruction of a table may be performed within a bounded number of operations based on the size of the table, the ratio implemented, and/or other characteristics.

Abstract: In response to a query of a decision tree, a first packed node of the decision tree is copied from a system memory into a direct memory access (“DMA”) memory. In response to copying the first packed node from the system memory into the DMA memory, copying is initiated of a second packed node of the decision tree from the system memory into the DMA memory, up to a limit of then-currently available space within the DMA memory. Concurrently with copying the second packed node from the system memory into the DMA memory, the first packed node is evaluated in the DMA memory. In response to evaluating the first packed node, the second packed node is evaluated in the DMA memory without waiting for additional copying of the second packed node from the system memory into the DMA memory.

Abstract: A method for selecting a command file is described. One or more command files coupled with a first device are accessed. Each command file of the one or more command files comprises one or more command file attributes. One or more device attributes associated with a second device are accessed. The one or more command file attributes and the one or more device attributes are compared to determine a correlation between the one or more command files and the second device. Based on the comparing, generating a ranked portion of the one or more command files according to the correlation.

Abstract: A method for faulty memory utilization in a memory system includes: obtaining information regarding memory health status of at least one memory page in the memory system; determining an error tolerance of the memory page when the information regarding memory health status indicates that a failure is predicted to occur in an area of the memory system affecting the memory page; initiating a migration of data stored in the memory page when it is determined that the data stored in the memory page is non-error-tolerant; notifying at least one application regarding a predicted operating system failure and/or a predicted application failure when it is determined that data stored in the memory page is non-error-tolerant and cannot be migrated; and notifying at least one application regarding the memory failure predicted to occur when it is determined that data stored in the memory page is error-tolerant.

Abstract: A device includes volatile memory; one or more non-volatile memory chips, each of which is for storing data moved from the volatile-memory; an interface for connecting to a backup power source arranged to temporarily power the volatile memory upon a loss of power from a primary power source; a controller in communication with the volatile memory and the non-volatile memory, wherein: the controller is programmed to move data from the volatile memory to the non-volatile memory chips upon a loss of power of the primary power source of the volatile memory; and parameters describing the volatile memory are stored in at least one of the non-volatile memory chips that store the data moved from the volatile memory. In some aspects the parameters include serial presence detect information.

Abstract: An illustrative embodiment of a computer-implemented process for managing a staging area creates the staging area for identified candidate cold objects, moves the identified candidate objects into the staging area, tracks application access to memory comprising the staging area and determines whether frequency of use information for a specific object exceeds a predetermined threshold. Responsive to a determination that the frequency of use information for the specific object exceeds a predetermined threshold, move the specific object into a regular area and determine whether a current time exceeds a predetermined threshold. Responsive to a determination that the current time exceeds a predetermined threshold, the computer-implemented process moves remaining objects from the staging area to a cold area.

Abstract: A method for queuing thread update buffers to enhance garbage collection. The method includes providing a global update buffer queue and a global array with slots for storing pointers to filled update buffers. The method includes with an application thread writing to the update buffer and, when filled, attempting to write the pointer for the update buffer to the global array. The array slot may be selected randomly or by use of a hash function. When the writing fails due to a non-null slot, the method includes operating the application thread to add the filled update buffer to the global update buffer queue. The method includes, with a garbage collector thread, inspecting the global array for non-null entries and, upon locating a pointer, claiming the filled update buffer. The method includes using the garbage collector thread to claim and process buffers added to the global update buffer queue.

Abstract: A memory management method and a memory controller and a memory storage apparatus using the same are provided. The method includes applying different detection biases to read data stored in physical pages of a rewritable non-volatile memory module and calculating the number of error bits according the read data. The method further includes estimating a value of a wearing degree of each physical page according to the calculated number of error bits and operating the rewritable non-volatile memory module according to the value of the wearing degree of each physical page. Accordingly, the method can effectively identify the wearing degree of the rewritable non-volatile memory module and operate the rewritable non-volatile memory module by applying a corresponding management mechanism, so as to prevent data errors.