Techniques described herein relate to systems and methods of data storage, and more particularly to providing layering of file system functionality on an object interface. In certain embodiments, file system functionality may be layered on cloud object interfaces to provide cloud-based storage while allowing for functionality expected from a legacy applications. For instance, POSIX interfaces and semantics may be layered on cloud-based storage, while providing access to data in a manner consistent with file-based access with data organization in name hierarchies. Various embodiments also may provide for memory mapping of data so that memory map changes are reflected in persistent storage while ensuring consistency between memory map changes and writes. For example, by transforming a ZFS file system disk-based storage into ZFS cloud-based storage, the ZFS file system gains the elastic nature of cloud storage.

Techniques described herein relate to systems and methods of data storage, and more particularly to providing layering of file system functionality on an object interface. In certain embodiments, file system functionality may be layered on cloud object interfaces to provide cloud-based storage while allowing for functionality expected from a legacy applications. For instance, POSIX interfaces and semantics may be layered on cloud-based storage, while providing access to data in a manner consistent with file-based access with data organization in name hierarchies. Various embodiments also may provide for memory mapping of data so that memory map changes are reflected in persistent storage while ensuring consistency between memory map changes and writes. For example, by transforming a ZFS file system disk-based storage into ZFS cloud-based storage, the ZFS file system gains the elastic nature of cloud storage.

A storage system includes a NAND storage media and a nonvolatile storage media as a write buffer for the NAND storage media. The write buffer is partitioned, where the partitions are to buffer write data based on a classification of a received write request. Write requests are placed in the write buffer partition with other write requests of the same classification. The partitions have a size at least equal to the size of an erase unit of the NAND storage media. The write buffer flushes a partition once it has an amount of write data equal to the size of the erase unit.

A memory system for accelerating graph neural network processing can include an on-host chip memory to cache data needed for processing a current root node. The system can also include a volatile memory interface between the host and non-volatile memory. The volatile memory can be configured to save one or more sets of next root nodes, neighbor nodes and corresponding attributes. The non-volatile memory can have sufficient capacity to store the entire graph data. The non-volatile memory can also be configured to pre-arrange the sets of next root nodes, neighbor nodes and corresponding attributes for storage in the volatile memory.

A memory system for accelerating graph neural network processing can include an on-host chip memory to cache data needed for processing a current root node. The system can also include a volatile memory interface between the host and non-volatile memory. The volatile memory can be configured to save one or more sets of next root nodes, neighbor nodes and corresponding attributes. The non-volatile memory can have sufficient capacity to store the entire graph data. The non-volatile memory can also be configured to pre-arrange the sets of next root nodes, neighbor nodes and corresponding attributes for storage in the volatile memory.

A memory system includes: a first memory module including first volatile memories; a second memory module including second volatile memories, non-volatile memories and a module controller; a memory controller controlling the first and second memory modules through second and third control buses, respectively; and a switch array electrically coupling the second and third control buses, wherein the module controller controls the switch array to electrically couple the second and third control buses in a backup operation for backing up data of the first volatile memories to the non-volatile memories, wherein the first and second memory modules include one or more first memory stacks and one or more second memory stacks, respectively, wherein the first volatile memories are stacked in the first memory stacks, and wherein the second volatile memories, the non-volatile memories and the module controller are stacked in the second memory stacks.

A memory system includes: a first memory module including first volatile memories; a second memory module including second volatile memories, non-volatile memories and a module controller; a memory controller controlling the first and second memory modules through second and third control buses, respectively; and a switch array electrically coupling the second and third control buses, wherein the module controller controls the switch array to electrically couple the second and third control buses in a backup operation for backing up data of the first volatile memories to the non-volatile memories, wherein the first and second memory modules include one or more first memory stacks and one or more second memory stacks, respectively, wherein the first volatile memories are stacked in the first memory stacks, and wherein the second volatile memories, the non-volatile memories and the module controller are stacked in the second memory stacks.

Processing a read request to read metadata from an entry of a metadata page may include: determining whether the metadata page is cached; responsive to determining the metadata page is cached, obtaining the first metadata from the cached metadata page; responsive to determining the metadata page is not cached, determining whether the requested metadata is in a metadata log of metadata changes stored in a volatile memory; and responsive to determining the metadata is the metadata log of metadata changes stored in the volatile memory, obtaining the requested metadata from the metadata log. Processing a write request that overwrites an existing value of a metadata page with an updated value may include: recording a metadata change in the metadata log that indicates to update the metadata page with the updated value; and performing additional processing during destaging that uses the existing value prior to overwriting it with the updated value.

Aspects of the present disclosure relate to reducing the latency of data deduplication. In embodiments, an input/output (IO) workload received by a storage array is monitored. Further, at least one IO write operation in the IO workload is identified. A space-efficient probabilistic data structure is used to determine if a director board is associated with the IO write. Additionally, the IO write operation is processed based on the determination.

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.