Writing time is shortened even in a memory writing time for each access unit is not constant. A writing time prediction information holding unit holds writing time prediction information for predicting the writing time in a plurality of memory modules for each of a plurality of memory modules. A request selecting unit preferentially selects a write request of which longer writing time is predicted out of a plurality of write requests requiring writing in each of a plurality of memory modules on the basis of the writing time prediction information.

A system and method for managing garbage collection in Solid State Drives (SSDs) in a Redundant Array of Independent Disks (RAID) configuration, using a RAID controller is described. A control logic can control read and write requests for the SSDs in the RAID configuration. A selection logic can select an SSD for garbage collection. Setup logic can instruct the selected SSD to enter a garbage collection setup phase. An execute logic can instruct the selected SSD to enter and exit the garbage collection execute phase.

Snapshots are processed without holding all write operations while the snapshots are being activated. Rather than holding all write operations until snapshots are activated, write operations may be allowed to proceed. Snapshot write processing may be temporarily suspended while the snapshots are being activated, including snapshot metadata being updated, while write operations received while the snapshots are being activated are logged. After snapshots have been activated for all logical LSUs for which snapshots were instructed to be activated, the logging of write operations may be stopped, and the logged write entries processed to determine whether any of the logged write operations require updating snapshot information of any logical storage elements (LSEs) of the LSUs. While the logged write operations are being processed, any write operations received from a host for an LSE having a logged write operation may be held until the held operation, or all held operations are processed.

Some examples describe data locality solutions for a hyperconverged computing system. In an example, a data request may be received at a Virtual Storage Appliance (VSA) node amongst a plurality of VSA nodes in a hyperconverged computing system. A determination may be made whether a remapped logical block address (LBA) associated with the data request is included on a first mapping layer on the VSA node. In response to a determination that the remapped LBA associated with the data request is present on the first mapping layer of the VSA node, the remapped LBA may be used to resolve the data request. In response to a determination that the remapped LBA associated with another data request is not present on the first mapping layer of the VSA node, a second mapping layer on the VSA node may be used to resolve the other data request.

A memory stores data, a memory interface circuit reads the data from the memory, and an arithmetic circuit performs a prescribed arithmetic operation on the data. A host interface circuit outputs an arithmetic request to the arithmetic circuit, and also outputs a reading instruction to the memory via the memory interface circuit, upon receipt of an arithmetic instruction from a host device. The host interface circuit receives, from the arithmetic circuit, an arithmetic result of the prescribed arithmetic operation performed on the data read from the memory via the memory interface circuit, and outputs the arithmetic result to the host device.

A solid state drive (SSD) device includes a first nonvolatile memory package, a second nonvolatile memory package, and a controller. The first nonvolatile memory package includes a first buffer chip and a plurality of first nonvolatile memory chips. The second nonvolatile memory package includes a plurality of second nonvolatile memory chips. The controller controls the first nonvolatile memory package and the second nonvolatile memory package. The first buffer chip communicates a first address signal and a first data with the controller, and selectively communicates the first data with one of the plurality of first nonvolatile memory chips and the plurality of second nonvolatile memory chips based on the first address signal.

A method and apparatus for operating a solid state drive is disclosed comprising receiving at least two commands from a host requiring an action by the solid state drive in a preliminary order, ordering the at least two commands based upon a quality of service classification for the at least two commands to a final order and executing the at least two commands on the solid state drive in the final order, wherein an operational parameter of the solid state drive is modified by at least one of the at least two commands.

A storage system includes a first storage apparatus including a first storage portion and a second storage portion, a second storage apparatus including a third storage portion and a fourth storage portion, and a storage management apparatus including a processor configured to control the first storage apparatus in an active state and control the second storage apparatus in a standby state, cause the first storage apparatus to execute first data relocation processing, cause the second storage apparatus to execute second data relocation processing, cause the first storage apparatus to suspend the first data relocation processing and cause the second storage apparatus to continue the second data relocation processing, switch the first storage apparatus from the active state to the standby state and switch the second storage apparatus from the standby state to the active state, and cause the first storage apparatus to resume the first data relocation processing.

A technique for scheduling access to a resource arranges tasks into multiple classes, where each class has a respective share and a respective priority. The share of a class sets an amount of access allocated to the class, and the priority sets an order in which the class can use its share, with higher priority classes getting access before lower-priority classes. The technique assigns latency-critical tasks, such as synchronous I/O tasks, to a first class having the highest priority and assigns bandwidth-critical tasks, such as background I/O processing, to a second class having a lower priority.

A storage network processing system includes a processor, a network interface and memory that stores operational instructions. The operation instructions enable the processor to receive a data object for storage and dispersed error encode the data object in accordance with dispersed error encoding parameters to produce a plurality of encoded data slices. The operation instructions further enable the processor to generate to determine a plurality of site slice sets from the plurality of encoded data slices, where each site slice set of the plurality of site slice sets includes a number of unique encoded data slices of the plurality of encoded data slices that is greater than or equal to a site write threshold value. The operation instructions further enable the processor to a designate one of a plurality of storage sites for each of the plurality of site slice sets and transmit each of the plurality of site slice sets to a corresponding designated one of the plurality of storage sites via the network.