Micron Technology Incorporated

John M Groves

Steven Moyer

Alexander Tomlinson

David Boles

Jacob Mulamootil Jacob

Systems and techniques for reducing probabilistic filter query latency are described herein. A query for a probabilistic filter that is stored on a first media may be received from a caller. In response to receiving the query, cached segments of the probabilistic filter stored on a second media may be obtained. Here, the probabilistic filter provides a set membership determination that is conclusive in a determination that an element is not in a set. The query may be executed on the cached segments resulting in a partial query result. Retrieval of remaining data of the probabilistic filter from the first media to the second media may be initiated without intervention from the caller. Here, the remaining data corresponds to the query and data that is not in the cached segment. The partial query results may then be returned to the caller.

Reducing probabilistic filter query latency

A system can include a memory device and a processing device operatively coupled with the memory device, to perform operations including receiving, from a first host application, a data object to store on the memory device and associating an object identifier with physical address ranges. The operations can further include associating the object identifier with a snapshot identifier to define a snapshot and mapping the physical address ranges to corresponding virtual address ranges of a second host application. The operations can also include responsive to receiving, from the first host application, a request to write to the data object recording, in a change log, an entry reflecting a change made to the data object, and responsive to receiving, from the first host application, a request to read a part of the data object, retrieving the part from the entry of the change log.

Shared memory snapshots

A system and method for updating a configuration of a host system so that the memory sub-system of the host system emulates performance characteristics of a target memory sub-system. An example system includes a memory sub-system; and a processor, operatively coupled with the memory sub-system, to perform operations comprising receiving a request to emulate a characteristic of a target memory sub-system, identifying a candidate configuration that generates a load on a memory sub-system of a host system to decrease a characteristics of the memory sub-system of the host system, and updating a configuration of the host system based at least on the candidate configuration, wherein the updated configuration changes the memory sub-system of the host system to emulate the characteristic of the target memory sub-system.

Emulating memory sub-systems that have different performance characteristics

A system and method for updating a configuration of a host system so that the memory sub-system of the host system emulates performance characteristics of a target memory sub-system. An example system determining a configuration of the host system, the host system comprising a memory sub-system; receiving, by a processing device, a request to emulate a characteristic of a target memory sub-system; analyzing a plurality of candidate configurations for the host system, wherein the plurality of candidate configurations comprises a candidate configuration that generates a load on the memory sub-system to decrease characteristics of the memory sub-system; and updating the configuration of the host system based on the plurality of candidate configurations, wherein the updated configuration changes the memory sub-system to emulate the characteristic of the target memory sub-system.

A KVS tree database and operations thereon are described herein. A KVS tree database is a multilevel tree that includes a base level and subsequent levels. The base level includes a heterogeneous kvset in a node, The heterogeneous kvset including entries for multiple KVS trees, such as a first entry for a first KVS tree and a second entry for a second KVS tree, The subsequent level includes a first node including a first homogeneous kvset for the first KVS tree and a second node including a second homogeneous kvset for the second KVS tree. Here, a homogeneous kvset includes nodes from only one KVS tree. The KVS tree database also includes a first determinative mapping of entries between the base level and the subsequent level and a second determinative mapping of entries between subsequent levels.

Heterogenous key-value sets in tree database

Various embodiments described herein provide for creation of a file that is backed by a requester-specified set of data storage objects. According to some embodiments, a request is received to create a new file on a file system that is backed by a specified set of data storage objects stored on a set of memory components. For example, the specified set of data storage objects can be associated with storage of one or more portions of an existing file stored on the set of memory components. In response to receiving the request to create the new file, a file data structure can be generated on the file system that represents the new file, where the file data structure comprises a mapping to the specified set of data storage objects. Subsequently, the request can be responded to with data that confirms creation of the new file on the file system.

File creation with requester-specified backing

A KVS tree and operations thereon are described herein. A key-value set (kvset) is received to store in a key-value data structure on at least one machine readable medium. The kvset includes a mapping of unique keys to values with the keys and the values of the kvset being immutable. The key-value data structure is organized as a tree with nodes of the tree including a temporally ordered sequence of kvsets. The kvset, once received, is written to a sequence of kvsets of a root-node of the tree.

KVS tree

Systems and techniques for stream selection from multi-stream storage devices. Notification of a KVS tree write request for a multi-stream storage device is received. The notification includes a KVS tree scope corresponding to data in the write request. A stream identifier (ID) is assigned to the write request based on the KVS tree scope and a stability value of the write request. The stream ID is returned to govern stream assignment to the write request, the stream assignment modifying a write operation of the multi-stream storage device.

Stream selection for multi-stream storage devices

Systems and techniques for collecting and using merge tree garbage metrics are described herein. A kvset is created for a node in a KVS tree. Here, a set of kvset metrics for the kvset are computed as part of the node creation. The kvset is added to the node. The node is selected for a compaction operation based on a metric in the set of kvset metrics. The compaction operation is performed on the node.

Merge tree garbage metrics

Systems and techniques for merge tree modifications for maintenance operations are described herein. A request for a KVS tree is received. Here, the KVS tree is a data structure including nodes and the nodes include a temporally ordered sequence of kvsets that store keys in sorted order. A parameter set for the KVS tree is received. The request is executed on the KVS tree by modifying operation of the KVS tree in accordance with the parameter.

Growing community of inventors

Austin, TX, United States of America

John M Groves