Abstract: A memory system includes a memory and a controller. The memory is configured to store a number of valid data in each of a plurality of logical blocks and a number of valid data for each of a plurality of banks in each of the logical blocks. The controller is configured to: select logical blocks of garbage collection target candidates based on the numbers of valid data in the logical blocks; calculate a maximum value among the numbers of valid data for the banks in each of the logical blocks of the garbage collection target candidates as a respective comparison value; and select one of the logical blocks of the garbage collection targets based on comparing the respective comparison values of the logical blocks of the garbage collection target candidates with each other.

Abstract: A memory system includes a memory and a controller. The memory is configured to store a number of valid data in each of a plurality of logical blocks and a number of valid data for each of a plurality of banks in each of the logical blocks. The controller is configured to: select logical blocks of garbage collection target candidates based on the numbers of valid data in the logical blocks; calculate a maximum value among the numbers of valid data for the banks in each of the logical blocks of the garbage collection target candidates as a respective comparison value; and select one of the logical blocks of the garbage collection targets based on comparing the respective comparison values of the logical blocks of the garbage collection target candidates with each other.

Abstract: A memory management device of an example of the invention controls writing into and reading from a main memory including a nonvolatile semiconductor memory and a volatile semiconductor memory in response to a writing request and a reading request from a processor. The memory management device includes a coloring information storage unit that stores coloring information generated based on a data characteristic of write target data to be written into at least one of the nonvolatile semiconductor memory and the volatile semiconductor memory, and a writing management unit that references the coloring information to determines a region into which the write target data is written from the nonvolatile semiconductor memory and the volatile semiconductor memory.

Abstract: According to one embodiment, the memory device includes a non-volatile memory, a volatile memory, and a controller. The controller carries out the transition to two different sleep states depending on a sleep instruction from the host device and saves sleep state information indicating the sleep state after the transition to the host-side storage device. Upon receiving a return instruction from the host device, the controller carries out return processing in accordance with the sleep state information stored in the host-side storage device.

Abstract: According to one embodiment, a memory system is connectable to a host including a first memory. The memory system includes a non-volatile second memory, a volatile third memory, and a controller. The controller uses the third memory as a work memory, and executes data transfer between the host and the second memory. The controller receives a first command to change a power mode from the host. The controller transfers first data to the first memory and transfers second data to the second memory in response to the receipt of the first command. The controller transmits a response of completion of data transfer. The first data and the second data are included in third data. The third data is data in the third memory.

Abstract: According to one embodiment, an information processing apparatus includes a host device, a memory system and a power supply circuit. The host device includes a volatile first memory and a first control circuit. The memory system includes a non-volatile second memory in which user data is stored and a second control circuit. The second control circuit executes transfer of the user data between the host device and the second memory. The first memory includes an area used by the second control circuit. The second control circuit uses the area as a buffer for the transfer. The first control circuit causes the power supply circuit to start and stop the power supply to the memory system. The first control circuit accesses, while the power supply to the memory system is stopped, the buffer.

Abstract: According to one embodiment, a memory system is connectable to a host including a first memory. The memory system includes a non-volatile second memory, a volatile third memory, and a controller. The controller uses the third memory as a work memory, and executes data transfer between the host and the second memory. The controller receives a first command to change a power mode from the host. The controller transfers first data to the first memory and transfers second data to the second memory in response to the receipt of the first command. The controller transmits a response of completion of data transfer. The first data and the second data are included in third data. The third data is data in the third memory.

Abstract: According to one embodiment, the memory device includes a non-volatile memory, a volatile memory, and a controller. The controller carries out the transition to two different sleep states depending on a sleep instruction from the host device and saves sleep state information indicating the sleep state after the transition to the host-side storage device. Upon receiving a return instruction from the host device, the controller carries out return processing in accordance with the sleep state information stored in the host-side storage device.

Abstract: A memory management device of an example of the invention controls writing into and reading from a main memory including a nonvolatile semiconductor memory and a volatile semiconductor memory in response to a writing request and a reading request from a processor. The memory management device includes a coloring information storage unit that stores coloring information generated based on a data characteristic of write target data to be written into at least one of the nonvolatile semiconductor memory and the volatile semiconductor memory, and a writing management unit that references the coloring information to determines a region into which the write target data is written from the nonvolatile semiconductor memory and the volatile semiconductor memory.

Abstract: In an embodiment, a device includes a first unit, a second unit, and a third unit. The first unit generates a write address representing a write position to sequentially store sequential data from a processor to a nonvolatile main memory. The second unit generates order information representing a degree of newness of write. The third unit writes sequentially writes the sequential data at the write address with the order information.

Abstract: A memory management device of an example of the invention controls writing into and reading from a main memory including a nonvolatile semiconductor memory and a volatile semiconductor memory in response to a writing request and a reading request from a processor. The memory management device includes a coloring information storage unit that stores coloring information generated based on a data characteristic of write target data to be written into at least one of the nonvolatile semiconductor memory and the volatile semiconductor memory, and a writing management unit that references the coloring information to determines a region into which the write target data is written from the nonvolatile semiconductor memory and the volatile semiconductor memory.

Abstract: According to one embodiment, a memory management device configured to manage a main memory including a nonvolatile semiconductor memory, the memory management device includes a sort module configured to sort, at a time of a data write operation in the nonvolatile semiconductor memory, data to write areas of the nonvolatile semiconductor memory, based on information of a frequency of write which is determined by a data attribute of the data, and a control module configured to write the sorted data in the nonvolatile semiconductor memory by an incremental-write type.