Pliops Ltd.

Samsung Electronics Co., Ltd.

Other

Samsung Israel Research Corporation

Moshe Twitto

Avner Dor

Jun Jin Kong

Elona Erez

Jun-Jin Kong

Yaron Shany

Yuval Rochman

Shay Landis

Avraham Poza Meir

Niv Dayan

Edward Bortnikov

Eran Hof

Roey Maor

Michael Pan

Shmuel Dashevsky

Eshcar Hillel

Hong Rak Son

Jong-Won Lee

Hong-Rak Son

Evgeny Blaichman

Chang Kyu Seol

Jung Soo Chung

Michael Erlihson

Young-Geon Yoo

Yoav Shereshevski

Michael Kara-Ivanov

Iddo Naiss

Dashevsky Shmuel

Guy Guetta

Tamar Weiss

Moshe Ben Ari

A method for updating a key-value (KV) storage system, the method includes (a) receiving a request to write a KV pair to the KV storage system; (b) storing the KV pair in an input buffer that is maintained in a volatile memory module of the KV storage system; (c) storing the KV pair in a separated KV database that is maintained in a non-volatile memory module of the KV storage system; (d) updating a B-tree that is stored in the non-volatile memory unit with (i) a key of the KV pair, (ii) a KV pair timestamp, and (iii) retrieval information for retrieving the KV pair from the separated KV database; and (e) maintaining a backup B-tree in the non-volatile memory module of the KV storage system, wherein the B-tree and the backup B-tree are separated from the separated KV database.

Separated database management

A method for performing a backup in relation to a separated database, the method includes creating, by a processing circuit, a new backup log structured merge (LSM) tree of the separated database, wherein the new backup LSM tree is associated with a new point in time (PIT) and belongs to a group of LSM trees that comprise a primary LSM tree and one or more backup LSM trees that are associated with different PITs, and share a key value (KV) database that is mutable and is separated from the group; wherein the creating comprises storing the new backup LSM tree to a destination.

Performing a backup in relation to a separated database

A method for managing a log structured merged (LSM) tree of key value (KV) pairs, the LSM tree is stored in a non-volatile memory, the method may include writing a current run from a buffer to a current run location within the LSM tree, the current run comprises current KV pairs; generating or receiving current fingerprints that are indicative of the current KV pairs; performing a run writing update of a management data structure (MDS) by adding to the MDS, mappings between the current KV pairs, the current fingerprints and a current run identifier; updating the LSM tree by merging at least some runs of the LSM tree; and performing a merge update of the MDS to represent the merging.

Managing a LSM tree of key value pairs that is stored in a non-volatile memory

A method for inserting a KV pair to a separated database, the method may include receiving a request to insert the KV pair to the separated database, wherein the separated database comprises a log structured merge (LSM) tree and KV database that is separated from LSM tree; determining whether the KV pair should be associated with a versioned LSM entry or with a non-versions LSM entry; and inserting the KV pair and a KV timestamp in the separated database according to the determining; wherein the inserting includes: storing a combination of the value and the KV timestamp in the KV database; defining an access key to the KV database; wherein the access key is based on the combination when determining that the KV pair should be associated with a versioned LSM; and wherein the access key is based on the key and not on the timestamp when determining that the KV pair should be associated with a non-versioned LSM.

A method for managing multiple checkpoints stored in a memory unit, the method may include (a) managing a checkpoint tree, by a memory controller; the checkpoint tree comprises reference nodes and active nodes; wherein a reference node of the reference nodes holds a snapshot of a parent checkpoint taken at the time that a child checkpoint was created from the parent checkpoint; wherein an active node of the active nodes that is associated with the parent node stores changes to the parent checkpoint introduced after a creation of the active node; and wherein the parent checkpoint and the child checkpoint belong to multiple checkpoints stored in the checkpoint tree; (b) receiving access requests to access key value (KV) pairs of one or more checkpoints of the multiple checkpoints; and (c) responding to the access requests based, at least in part, on the checkpoint tree.

Checkpoints management by a memory controller

A method for error correction of logical pages of an erase block of a solid state drive (SSD) memory, the method may include determining an erase block score of the erase block, wherein the calculating is based on a program erase (PE) cycle of the erase block and one or more erase block error correction parameter; determining, based on (a) the erase block score, and (b) a mapping between the erase block score and one or more page error correction parameters for each page type out of multiple pages types, the one or more page error correction parameter for each page type; and allocating, within each page of the erase block, an overprovisioning space and an error correction space, based on at least one page error correction parameter related to a page type of the page.

Efficient redundancy management in key-value NAND flash storage

A method for managing a log structured merged (LSM) tree of key value (KV) pairs, the LSM tree is stored in a non-volatile memory, the method may include merging runs of the LSM tree to provide merged runs; writing merged runs to the non-volatile memory; adding new runs to the LSM tree, wherein the adding comprises writing runs to the non-volatile memory; and updating at least one management data structure (MDS) to reflect the merging and the adding; wherein an MDS of the at least one MDS stores a mapping between keys of the KV pairs of the LSM tree, fingerprints associated with the KV pairs of the LSM tree, and compressed run identifiers that identify runs of the LSM tree.

There may be provided, systems, method and non-transitory computer readable media for accessing a key value pair stored in a solid state drive (SSD) memory, the method may include calculating, by a SSD memory controller and based on an input key, a first bucket identifier and a first inter-bucket value; determining a block cluster that stores the key pair value, based on the first bucket identifier, the first inter-bucket value and first metadata of a first data structure; calculating, based on the input key, a second bucket identifier and a second inter-bucket value; determining at least one of a key pair value retrieval information and a representative key pair value retrieval information, based on the second bucket identifier, the second inter-bucket value and second metadata of a second data structure; wherein the second data structure is allocated to the block cluster; wherein the second metadata comprises second logical slots, a second slot locator and second collision separation metadata; wherein at least the second slot locator comprise metadata only on representative key-pair values that are a subset of multiple key-pair values stored in the block cluster; and retrieving at least the value of the key pair value based on the at least one of the key pair value retrieval information and the representative key pair value retrieval information.

Data base and solid state disk (SSD) controller

A method for accessing a block of information stored in a SSD memory, the method may include obtaining, by an SSD controller, an identifier associated with the block of information; accessing, using the identifier, a first data structure that maps identifiers to cluster maps; wherein the first data structure comprises block sequence metadata, wherein for at least one cluster map, the block sequence metadata comprises a sequence identifier of a sequence of blocks of information that are sequentially written to the SSD memory and are stored together in a cluster of the SSD memory; accessing a cluster map of a cluster that is associated with the sequence provide block retrieval information; and retrieving the block of information from the SSD memory, using the block retrieval information.

Efficient FTL implementation with compression

A method for protecting objects, the method may include receiving, by a storage controller, a request to write a new object to a storage-system that may include multiple nodes, each node may include at least one storage element; the new object may include a key value pair; writing the new object to a target node and to another node of the multiple nodes; and generating a new stripe that may include multiple sets of objects, different sets of objects are stored at different nodes of the multiple nodes, a certain set of objects of the multiple sets of objects may include the new object and is stored in a first node of the target node and the other node, any set of objects of the multiple sets of objects is reconstructible using other sets of objects of the multiple set of objects.

Logical raid

There may be provided, systems, method and non-transitory computer readable media for accessing a key value pair stored in a solid state drive (SSD) memory, the method may include calculating, by a SSD memory controller and based on an input key, a first bucket identifier and a first inter-bucket value; determining a block cluster that stores the key pair value, based on the first bucket identifier, the first inter-bucket value and first metadata of a first data structure; calculating, based on the input key, a second bucket identifier and a second inter-bucket value; determining key pair value retrieval information, based on the second bucket identifier, the second inter-bucket value and second metadata of a second data structure; wherein the second data structure is allocated to the block cluster; and retrieving at least the value of the key pair value based on the key pair value retrieval information.

Solid state disk (SSD) controller and database

A method for accessing a key-value pair stored in a SSD memory, the method may include receiving, by a SSD memory controller, an input key; applying a first hash function on an input key to provide a first address; reading, using the first address, an indicator that indicates whether (a) the input key is associated with a group of key-value pairs or whether (b) the input key is associated only with the key-value pair; retrieving, from the SSD memory, the values of the group associated with the input key, and extracting the value of the key-value pair, when the indicator indicates that the input key is associated with the group; and retrieving, from the SSD memory, a value of a key-value pair, when the indicator indicates that the input key is associated with the key-value pair.

Method for retrieving key value pairs and groups of key value pairs

A memory system includes a nonvolatile memory device having a plurality of physical sectors, a mapping table, and a memory controller including a plurality of hash functions. The memory controller is configured to access the physical sectors using the mapping table and the hash functions. The memory controller is configured to receive a sequence of logical block addresses (LBAs) from a host and logical sector data for each of the LBAs, generate a first virtual address by operating a selected hash function among the hash functions on a first logical block address (LBA) among the sequence, compress the logical sector data to generate compressed data, and store the compressed data in a first physical sector among the physical sectors that is associated with the first virtual address.

Nonvolatile memory devices and methods of controlling the same

A method of operating a storage device including a nonvolatile memory can be provided by receiving, from a host, address change information including changing logical addresses for data to be stored in the nonvolatile memory. Physical addresses can be sequentially allocated to the changing logical addresses included in the address change information to provide a first journal. A portion of at least one physical address allocated to the changing logical addresses can be removed to provide a second journal and the second journal can be stored in the nonvolatile memory.

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Ramat Gan, Israel

Moshe Twitto