Abstract: Methods and apparatuses for parallel processing data are disclosed. One method includes reading items of data from a memory using at least memory access address, confirming items of data with the same memory address among the read items of data, and masking the confirmed items of data other than one of the confirmed items of data. A correction value is generated for the memory access address using the confirmed items of data, and an operation is performed on data that has not been masked using the confirmed items of data and the correction value. Data obtained by operating on the data that has not been masked is stored as at least on representative data item for the data items with the same memory address. A schedule of a compiler of a processor is adjusted by performing bypassing of memory access address alias checking for at least one memory access address.

Abstract: A solid-state storage device (SSD) controller is provided for use with an SSD. The SSD includes a plurality of memory cells, such as non-volatile memory (NVM) cells. The SSD controller comprises a processor and a memory storing statements and instructions for execution by the processor to perform a method of configuring the memory cells. In a dynamic configuration implementation in which at least a subset of the NVM cells are configured in a first bit retention mode, the method includes: monitoring data activity in relation to the SSD; and dynamically reconfiguring the subset of the NVM cells in a second bit retention mode based on the monitored data activity, such as whether data traffic comprises a majority of read activity or write activity. In a static configuration implementation, the method includes receiving at least one performance characteristic for the NVM cells; and configuring the subset of the NVM cells in a first bit retention mode based on the received at least one performance characteristic.

Abstract: A method of operating a memory system, including a memory device, includes managing program order information of the memory device based on a program order stamp (POS) indicating a relative temporal relationship between program operations of a plurality of memory groups that are included in the memory device. The method includes generating a first mapping table that stores a read voltage offset and an upper POS corresponding to the read voltage offset, by using a plurality of voltage levels that are sequentially decreased or reduced, and generating a second mapping table that stores the read voltage offset and a lower POS corresponding to the read voltage offset, by using a plurality of voltage levels that are sequentially increased. A read voltage for performing a read operation on the memory device is variably determined based on the first and second mapping tables and the program order information.

Abstract: A data processing system and methods for performing cache eviction are disclosed. An exemplary method includes maintaining a metadata set for each cache unit of a cache device, wherein the cache device comprises a plurality of cache units, each cache unit having a plurality of segments, calculating a score for each metadata set, and arranging the metadata sets in a list in ascending order from lowest score to highest score. The exemplary method further includes in response to determining that a cache eviction is to be performed, selecting a cache unit corresponding to the metadata set in the list having the lowest score, without recalculating a score for any of the metadata set, and evicting the selected cache unit. The metadata nay include, for example, segment count metadata, validity metadata, last access time (LAT) metadata, and hotness metadata.

Abstract: Deduplicated data storage is provided by presenting a virtual volume mapped by a translation table to a physical volume of a physical data storage system. The translation table maps sets of ranges of duplicate data blocks of the virtual volume to corresponding individual ranges of shared data blocks of the physical volume. A hash table for identifying duplicate data is indexed by a portion of a hash value calculated from newly written data blocks, and has entries each identifying an address alignment of the corresponding data block. In operation, existing entries are replaced with new entries for colliding data blocks having better address alignment, promoting wider address-space separation of the entries. Upon occurrence of a hit in the hash table, for a given data block in a range of newly written data blocks, data blocks of the range are compared to corresponding blocks in a range identified by the hit to maximize a size of a region to be identified by the translation table as duplicate data.

Abstract: Methods and apparatus are provided for multi-tier detection and decoding in flash memory devices. Data from a flash memory device is processed by obtaining one or more read values for at least one bit in a given page of the flash memory device; converting the one or more read values for the at least one bit to a reliability value; performing an initial decoding of the at least one bit in a given page using the reliability value; and performing an additional decoding of the at least one bit in the given page if the initial decoding is not successful, wherein the additional decoding uses one or more of additional information for the given page and at least one value for at least one bit from at least one additional page.

Abstract: A data processing system and methods for performing cache eviction are disclosed. An exemplary method includes maintaining a metadata set for each cache unit of a cache device at a sub-cache unit granularity, wherein the cache device comprises a plurality of cache units, each cache unit having a plurality of segments, wherein the cache device is accessible by a cache client at a segment granularity. The exemplary method further includes in response to determining that a cache eviction is to be performed, selecting a predetermined number of cache units from the plurality of cache units, determining a score for each of the selected cache units based on the respective metadata set maintained at the sub-cache unit granularity, and evicting one or more of the selected predetermined number of cache units based on their scores. The metadata may include, for example, last access time (LAT) metadata, an access count, and hotness metadata, and metadata may be maintained at a segment or a segment group granularity.

Abstract: A data processing system and methods for performing cache eviction are disclosed. An exemplary method includes maintaining a metadata set for each cache unit of a cache device comprising a plurality of cache units, each cache unit having a plurality of segments. In response to determining that a cache eviction is to be performed, a cache unit is evicted based on its metadata set. The exemplary method includes selecting one or more segments of the evicted cache unit to copy to a second cache unit based on the metadata set of the evicted cache unit, copying the selected one or more segments to the second cache unit, and writing the second cache unit to a storage device. The metadata set may include deletion hints (DH) to indicate valid segments, last access time (LAT) or age based metadata, an access count, or a score for each segment based on the metadata set.

Abstract: A computer-implemented method is provided which includes: assigning data having a first heat to a first data stream, assigning data having a second heat to a second data stream, determining an anticipated throughput of each of the first and second data streams, assigning a first number of logical erase blocks of non-volatile memory to the first data stream based on the anticipated throughput of the first data stream, and assigning a second number of logical erase blocks of non-volatile memory to the second data stream based on the anticipated throughput of the second data stream. The number of logical erase blocks assigned to the data streams may be statically assigned, or may be adjusted dynamically based on at least one of temporal stream throughput, stream stall events, a current workload, or other factors. The non-volatile memory may include NAND flash memory, and wear leveling may be performed on all open logical erase blocks prior to assigning the first and second numbers of erase blocks.

Abstract: A method for transmitting and receiving data between a micro processing unit (MPU) and a memory operating with different operating voltages in a programmable logic controller (PLC) is provided. In one embodiment, the method includes outputting, by the MPU, a chip select (CS) signal and an address signal to read requested data from the memory, outputting, by an OR gate, an activation signal for activating a data input buffer, the OR gate receiving the CS signal and the address signal, and outputting, by an access signal output buffer, a memory access signal for operation of the memory, the access signal output buffer receiving the CS signal and the address signal. The method further includes outputting the requested data to the data input buffer, and outputting, by the data input buffer, the requested data to the MPU when the requested data is received by the data input buffer from the memory.

Abstract: An administrator provisions a virtual disk in a remote storage platform and defines policies for that virtual disk. A virtual machine writes to and reads from the storage platform using any storage protocol. Virtual disk data within a failed storage pool is migrated to different storage pools while still respecting the policies of each virtual disk. Snapshot and revert commands are given for a virtual disk at a particular point in time and overhead is minimal. A virtual disk is cloned utilizing snapshot information and no data need be copied. Any number of Zookeeper clusters are executing in a coordinated fashion within the storage platform, thus increasing overall throughput. A timestamp is generated that guarantees a monotonically increasing counter, even upon a crash of a virtual machine. Any virtual disk has a “hybrid cloud aware” policy in which one replica of the virtual disk is stored in a public cloud.

Abstract: A microprocessor of a solid state memory protects the contents of the solid state memory by comparing a sequence of requests for access to physical blocks of the solid state memory with a predetermined sequence of requests to verify the sequence of requests, and by responding to additional requests for access to the physical blocks of the solid state memory to decrypt and transfer requested files stored therein when the sequence of requests equals the predetermined sequence of requests, thereby verifying the sequence of requests. The predetermined sequence of requests is associated with a plurality of virtual files that can be selected, in a particular sequence, to simulate a request for access to physical blocks of the solid state memory, while the predetermined sequence of requests is stored in a configuration file of the solid state memory in correspondence with an identifier of additional protected files.

Abstract: Systems and methods for retaining data are disclosed in which refresh copy operations are performed on data stored in non-volatile solid-state memory. A controller may be configured to maintain a list of physical memory locations, the list sorted by a least recently used criterion. The controller may select a first entry from a top of the list and perform a refresh operation to copy data stored in a current physical memory location associated with the first entry to a new physical memory location, and may remove the first entry from the top of the list and add a new entry associated with the new physical memory location to a bottom of the list. The controller may repeat the select, perform, remove and add steps for a plurality of entries in the list, and the steps may be timed such that all refresh operations are performed for all of the plurality of entries within a set period of time.

Abstract: A method, computer program product, and computer system are disclosed for disk management in a distributed storage system, wherein the distributed storage system comprises a plurality of disks within a main disk ring, and the disks store target data. In one embodiment, the method comprises dividing the target data into cold target data and hot target data, and grouping one or more disks within the main disk ring into a cold data disk ring and the remaining one or more disks within the main disk ring into a hot data disk ring, based on the cold target data's and the hot target data's positions on disks. The method further comprises migrating the cold target data on disks not within the cold data disk ring onto disks within the cold data disk ring while migrating the hot target data on disks not within the hot data disk ring onto disks within the hot data disk ring, and reducing a spinning rate of disks within the cold data disk ring.

Abstract: An administrator provisions a virtual disk in a remote storage platform and defines policies for that virtual disk. A virtual machine writes to and reads from the storage platform using any storage protocol. Virtual disk data within a failed storage pool is migrated to different storage pools while still respecting the policies of each virtual disk. Snapshot and revert commands are given for a virtual disk at a particular point in time and overhead is minimal. A virtual disk is cloned utilizing snapshot information and no data need be copied. Any number of Zookeeper clusters are executing in a coordinated fashion within the storage platform, thus increasing overall throughput. A timestamp is generated that guarantees a monotonically increasing counter, even upon a crash of a virtual machine. Any virtual disk has a “hybrid cloud aware” policy in which one replica of the virtual disk is stored in a public cloud.

Abstract: An electronic device includes a semiconductor memory device. The semiconductor memory device includes: a word line driving unit for driving a plurality of word lines; a first circuit area including a first cell array arranged at one side of the word line driving unit; a second circuit area including a second cell array arranged at the other side of the word line driving unit; a bias voltage generation unit arranged between the first cell array and the second cell array; a first read control unit; and a second read control unit. The first and second cell arrays include storage cells having variable resistance elements, and the bias voltage generation unit generates a bias voltage based on currents flowing through a first reference resistance element included in the first cell array and a second reference resistance element included in the second cell array.

Abstract: A memory system includes a memory device, the memory device including a memory cell array and a compression encoder, the memory cell array including a first plurality of multi level cells (MLCs). The memory device is configured to generate a first partial page by performing one or more first sensing operations on the first plurality of MLCs using one or more first reference voltages, output the first partial page, generate a second partial page by performing a second sensing operation on the first plurality of MLCs based on a second reference voltage, the second reference voltage having a different voltage level than the one or more first reference voltages, generate a compressed second partial page by compressing the second partial page using the compression encoder, and output the compressed second partial page.

Abstract: An administrator provisions a virtual disk in a remote storage platform and defines policies for that virtual disk. A virtual machine writes to and reads from the storage platform using any storage protocol. Virtual disk data within a failed storage pool is migrated to different storage pools while still respecting the policies of each virtual disk. Snapshot and revert commands are given for a virtual disk at a particular point in time and overhead is minimal. A virtual disk is cloned utilizing snapshot information and no data need be copied. Any number of Zookeeper clusters are executing in a coordinated fashion within the storage platform, thus increasing overall throughput. A timestamp is generated that guarantees a monotonically increasing counter, even upon a crash of a virtual machine. Any virtual disk has a “hybrid cloud aware” policy in which one replica of the virtual disk is stored in a public cloud.

Abstract: Methods, systems, and computer program products are provided that enable a first application (i.e., a caller application) to call a second application (i.e., a callee application) to perform a function in a manner such that the first application may be dehydrated during the call. Dehydrating includes terminating execution of an instance of the first application, and freeing memory space in a memory of a mobile device that stored the instance of the first application. In such case, the second application may be active while the first application is no longer present in memory. The second application is enabled to respond to the call, causing the first application to be rehydrated. The first application continues execution at a location where the first application was dehydrated, and receives the response to the call.

Abstract: Persistent storage for a master copy is provided using operation numbers. A master copy can include a persistent key-value store such as a B-tree with references to corresponding data. When provisioning a slave copy, the master copy sends a point-in-time copy of the B-tree to the slave copy, which stores a copy of the B-tree, allocates the necessary space, and updates the references of the B-tree to point to a local storage before the data is transferred. When writing the data to persistent storage, a snapshot created on the master copy is an operation that is replicated to the slave copy. The snapshot is generated using a volume view that includes changes to chunks of data of the master copy since a previous snapshot, as determined using the operation number for the previous snapshot. Data (and metadata) for the snapshot is written to persistent storage while new EO operations are processed.