Abstract: A memory system according to an embodiment of the present invention comprises: speed of processing for searching through management tables is increased by providing a forward lookup table for searching for, respectively in track and cluster units, from a logical address, a storage device position where data corresponding to the logical address and a reverse lookup table for searching for, from a position of the storage device, a logical address stored in the position and linking these tables.

Abstract: A memory system includes a controlling unit that configured to control data transfer between the first and the second memory. The controlling unit executes copy processing for, after reading out data stored in a first page of the second memory to the first memory, writing the data in a second page of the second memory, determines, when executing the copy processing, whether the error correction processing for the data read out from the first page is successful, stores, when the error correction processing is successful, corrected data in the first memory and writes the corrected data in the second page, and reads out, when the error correction processing is unsuccessful, the data from the first page to the first memory and writes the data not subjected to the error correction processing in the second page.

Abstract: A memory system includes a nonvolatile semiconductor memory having blocks, the block being data erasing unit; and a controller configured to execute; an update processing for; writing superseding data in a block, the superseding data being treated as valid data; and invalidating superseded data having the same logical address as the superseding data, the superseded data being treated as invalid data; and a compaction processing for; retrieving blocks having invalid data using a management tablet the management table managing blocks in a linked list format for each number of valid data included in the block; selecting a compaction source block having at least one valid data from the retrieved blocks; copying a plurality of valid data included in the compaction source blocks into a compaction target block; invalidating the plurality of valid data in the compaction source blocks; and releasing the compaction source blocks in which all data are invalidated.

Abstract: A memory system includes a volatile first storing unit, a nonvolatile second storing unit, and a controller. The controller performs data transfer, stores management information including a storage position of data stored in the second storing unit into the first storing unit, and performs data management while updating the management information. The second storing unit stores management information in a latest state and a storage position of the management information. The storage position information is read by the controller during a startup operation of the memory system and includes a second pointer indicating a storage position of the management information in a latest state and a first pointer indicating a storage position of the second pointer. The first pointer is stored in a fixed area in the second storing unit and the second pointer is stored in an area excluding the fixed area in the second storing unit.

Abstract: According to one embodiment, a first program code including a plurality of variables is converted to a second program code to be executed by a multi-core processor including a plurality of cores. Specifically, an access pattern of each variable in the first program code is decided. All variables in the first program code are classified into a plurality of groups each of which variables belong to the same access pattern. A member structure of each group having variables belonging to the same access pattern is created. Each member structure includes variables of one group. A route-pointer indicating an address (in a memory) of variables of the member structure is created. The variables in the first program code are converted to the member structure and the route-pointer (in the second program code) that indicate the variables. The second program code is outputted to the multi-core processor.

Abstract: According to one embodiment, a memory system includes a nonvolatile semiconductor memory include a first area, and a second area smaller than the first area; and a controller configured to control data stored in the nonvolatile semiconductor memory, wherein the nonvolatile semiconductor memory is configured to store a first data accessible by a host command and to a second data inaccessible by the host command, and when receiving the host command, the controller writes the second data of the first area within the second area and initializes a first address information related the first data.

Abstract: A memory system includes a first, second and third storing area included in a volatile semiconductor memory, and a controller that allocates the storage area of the nonvolatile semiconductor memory to the second storing area and the third storing area in a logical block unit associated with one or more blocks. First and second management units respectively manage the second and third storing areas. The second management unit has a size larger than that of the first management unit. When flushing data from the first to the second or third storing areas, the controller collects, from at least one of the first, second and third storing areas, data other than the data to be flushed and controls the flushing of the data such that a total of the data is a natural number times as large as the block unit as much as possible.

Abstract: A memory system includes a volatile first storing unit, a nonvolatile second storing unit in which data is managed in a predetermined unit, and a controller that writes data requested by a host apparatus in the second storing unit via the first storing unit and reads out data requested by the host apparatus from the second storing unit to the first storing unit and transfers the data to the host apparatus. The controller includes a management table for managing the number of failure areas in a predetermined unit that occur in the second storing unit and switches, according to the number of failure areas, an operation mode in writing data in the second storing unit from the host apparatus.

Abstract: According to one embodiment, a program converting device includes an access attribute determining unit, a non-sharing target classifying unit, and a converting unit. The access attribute determining unit calculates exclusive accesses from memory accesses by threads forming a source program and determines a memory access using a cache memory among the calculated exclusive accesses. The non-sharing target classifying unit determines an access data item that does not share a cache line with another access data item among the access data items that are accessed using the cache memories. The converting unit inserts a process that does not share the cache line into the source program based on the determination result of the non-sharing target classifying unit.

Abstract: According to one embodiment, a memory system includes a nonvolatile semiconductor memory include a first area, and a second area smaller than the first area; and a controller configured to control data stored in the nonvolatile semiconductor memory, wherein the nonvolatile semiconductor memory is configured to store a first data accessible by a host command and to a second data inaccessible by the host command, and when receiving the host command, the controller writes the second data of the first area within the second area and initializes a first address information related the first data.

Abstract: A memory system according to an embodiment of the present invention comprises: a data managing unit 120 is divided into a DRAM-layer managing unit 120a, a logical-NAND-layer managing unit 120b, and a physical-NAND-layer managing unit 120c to independently perform management of a DRAM layer, a logical NAND layer, and a physical NAND layer using the respective managing units to thereby perform efficient block management.

Abstract: A memory system according to an embodiment of the present invention comprises: speed of processing for searching through management tables is increased by providing a forward lookup table for searching for, respectively in track and cluster units, from a logical address, a storage device position where data corresponding to the logical address and a reverse lookup table for searching for, from a position of the storage device, a logical address stored in the position and linking these tables.

Abstract: A memory system includes a first storing area included in a volatile semiconductor memory, a second and a third storing area included in a nonvolatile semiconductor memory, a controller that allocates the storage area of the nonvolatile semiconductor memory to the second storing area and the third storing area in a logical block unit associated with one or more blocks. The second storing area is configured to be managed with a first management unit. The third storing area is configured to be managed with a second management unit, a size of the second management unit being larger than a size of the first management unit.

Abstract: A memory system includes a volatile first storing unit, a nonvolatile second storing unit, and a controller. The controller performs data transfer, stores management information including a storage position of data stored in the second storing unit into the first storing unit, and performs data management while updating the management information. The second storing unit stores management information in a latest state and a storage position of the management information. The storage position information is read by the controller during a startup operation of the memory system and includes a second pointer indicating a storage position of the management information in a latest state and a first pointer indicating a storage position of the second pointer. The first pointer is stored in a fixed area in the second storing unit and the second pointer is stored in an area excluding the fixed area in the second storing unit.

Abstract: A memory system in which speed of processing for searching through management tables is increased by providing a forward lookup table for searching for, respectively in track and cluster units, from a logical address, a storage device position where data corresponds to the logical address, and a reverse lookup table for searching for, from a position of the storage device, a logical address stored in the position. These forward and reverse lookup tables are linked.

Abstract: It is to provide: a generation unit configured to generate one or more reference relationship pairs with reference certainty information of “uncertainty” as presentation information based on first reference relationship information showing whether it is “certain” for the reference data to refer the referenced data or it is “uncertain” for the reference data to refer the referenced data, every reference relationship pair formed with reference data and referenced data; and a conversion unit configured to convert the first reference relationship information into second reference relationship information using an input of a reference relationship for presentation information and reference dependence relationship information showing a dependence relationship between reference relationship pairs.

Abstract: A memory system according to an embodiment of the present invention comprises: a memory amount required for management table creation is reduced by adopting a nonvolatile semiconductor memory including a plurality of parallel operation elements respectively having a plurality of physical blocks as units of data erasing and a controller that can drive the parallel operation elements in parallel and has a number-of-times-of-erasing managing unit that manages the number of times of erasing in logical block units associated with a plurality of physical blocks driven in parallel.

Abstract: A memory system includes a management-information restoring unit. The management-information restoring unit determines whether a short break has occurred referring to a pre-log or a post-log in a NAND memory. The management-information restoring unit determines that a short break has occurred when the pre-log or the post-log is present in the NAND memory. In that case, the management-information restoring unit determines timing of occurrence of the short break, and, after selecting a pre-log or a post-log used for restoration, performs restoration of the management information reflecting these logs on a snapshot. Thereafter, the management-information restoring unit applies recovery processing to all write-once blocks in the NAND memory, takes the snapshot again, and opens the snapshot and the logs in the past.

Abstract: According to one embodiment, a program converting device includes an access attribute determining unit, a non-sharing target classifying unit, and a converting unit. The access attribute determining unit calculates exclusive accesses from memory accesses by threads forming a source program and determines a memory access using a cache memory among the calculated exclusive accesses. The non-sharing target classifying unit determines an access data item that does not share a cache line with another access data item among the access data items that are accessed using the cache memories. The converting unit inserts a process that does not share the cache line into the source program based on the determination result of the non-sharing target classifying unit.

Abstract: A memory system includes a volatile first storing unit, a nonvolatile second storing unit, and a controller. The controller performs data transfer, stores management information including a storage position of the data stored in the second storing unit into the first storing unit, and performs data management while updating the management information. The second storing unit has a management information storage area for storing management information storage information including management information in a latest state and a storage position of the management information. The storage position information is read by the controller during a startup operation of the memory system and includes a second pointer indicating a storage position of management information in a latest state in the management information storage area and a first pointer indicating a storage position of the second pointer.