Abstract: According to one embodiment, a storage system includes a host computer and a storage device. The host computer includes a file system which has a structure for managing a file by using a management structure and metadata that manage correspondence between stored data and the storage position of the data on the file system, and bitmap information for identifying a unit area that holds valid data and other unit areas. The host computer manages the management structure and the metadata, and manages the bitmap information. The storage device manages information for identifying a unit area that holds valid data in the storage device and other areas by using the bitmap information used for management of the file system shared with the host computer.

Abstract: According to one embodiment, a data processing device including a user space including a user space thread including a plurality of coroutines and a file system. The file system is configured to: allocate a plurality of processes generated by an application to the plurality of coroutines; check the plurality of coroutines in order; when a first process included in the plurality of processes is allocated to a first coroutine included in the plurality of coroutines, write a first IO request based on the first process in a submission queue; and when the submission queue is filled, or when checking the plurality of coroutines is finished, transmit the first IO request written in the submission queue to a storage device.

Abstract: According to one embodiment, a data processing device including a user space including a user space thread including a plurality of coroutines and a file system. The file system is configured to: allocate a plurality of processes generated by an application to the plurality of coroutines; check the plurality of coroutines in order; when a first process included in the plurality of processes is allocated to a first coroutine included in the plurality of coroutines, write a first IO request based on the first process in a submission queue; and when the submission queue is filled, or when checking the plurality of coroutines is finished, transmit the first IO request written in the submission queue to a storage device.

Abstract: An obtaining unit obtains a first-type request which includes address information corresponding to a writing instruction or a reading instruction with respect to a value. A converting unit converts the first-type request into a second-type request which includes a key having a combination of the address information and version information. The version information is updated every time the writing instruction is issued with the position indicated by the address information as the writing position. Based on the second-type request, a control unit either performs a writing operation for writing the value corresponding to the key in a key value store type database including a plurality of storage devices each of which is set either as a master storage device or as a slave storage device, or performs a reading operation for reading the value corresponding to the key from the database.