Vast Data Ltd.

Emc IP Holding Company LLC

Oren Ashkenazi

Avi Goren

Ohad Ben-Yehuda

Uri Weissbrem

Adi Bar Shalom

Asaf Levy

Eyal Gordon

Asaf Weissman

Zeev Shusterman

Lior Zilpa

Ohad Shamir

German Goft

Ivan Rubin

Nadav Halwany

Benny Lodman

A method for asynchronous replication, the method includes initiating a current replication cycle of multiple files system entities (FSEs) that include primary FESs originated from a primary storage system (PSS) and external FSEs that originated from one or more external storage systems (ESSs), each external storage system differs from the primary storage system and differs from a secondary storage system. The initiating is followed by sending primary content and external content from the primary storage system to the secondary storage system. The primary content is indicative of differences in the primary FSEs between a previous replication cycle point in time (PIT) and a current replication cycle PIT. For each external FSE, an external content is indicative of differences in the external FSEs between (a) a last external FSE snapshot that preceded the previous replication cycle PIT and was generate by an external FSE snapshot process, and (b) a last external FSE snapshot that preceded the current replication cycle PIT and was generate by the external FSE snapshot process. The external FSE snapshot process and a process for generating the current replication cycle are not mutually synchronized.

Cascaded replication

A method for responding to a query, the method may include (a) receiving, by a storage system compute element, a query that comprises one or more conditions related to a content of at least one data unit (DU); (b) searching, based on the one or more conditions and on a condition fulfillment information (CFI), for one or more irrelevant groups of DUs to be skipped during the responding to the query; wherein the one or more irrelevant groups of DUs belong to multiple stored groups of DUs that are stored in the storage system; wherein an irrelevant group of DU does not comprise, according to the CFI, any DU that fulfills the one or more conditions; and (c) generating a response to the query based on an outcome of the searching.

Query cached filter

A method for determining a progress of an execution of a task, the method may include accessing only a portion of a shared task status data structure that (a) is associated with the task, wherein the task is executed by a first plurality of compute elements, and (b) comprises multiple hierarchical levels; wherein an entry of a certain hierarchical level represents an aggregate progress associated with multiple entries of the another hierarchical level; the certain hierarchical level is higher than the other hierarchical level; and determining the progress of the execution of the task based on a content of the portion.

Distributed task progress report

In one embodiment, an apparatus comprises a source system comprising a processing device coupled to memory. The processing device is configured to obtain an IO operation corresponding to an address of the source system. The IO operation comprises first user data. The processing device is further configured to store metadata associated with the IO operation in a first journal barrier of a replication journal of the source system and to close the first journal barrier. The processing device is further configured to determine that the first user data associated with the IO operation is missing from the first journal barrier and to obtain second user data from the address. The processing device is further configured to identify an interval from the first journal barrier to a second journal barrier and to provide the first journal barrier and the interval to a destination system.

Journal barrier consistency determination

A method for snapshot reversion, the method may include initializing a recovery of a storage system, from a failure that stopped a replication of a failed replication snapshot to an other storage system; wherein the other storage system reverted to an older snapshot not stored in the storage system; and reverting to the older snapshot, by the storage system using older snapshot metadata and data received from the storage system; wherein the older snapshot data may include a non-existing indication for a snapshot segment that existed in a snapshot that followed the older snapshot and not exists at the older snapshot, and wherein the data may include one or more older snapshot segments; wherein the reverting to the older snapshot is executed without undoing changes that were made since the older snapshot.

Replication for snapshot reversion

A method for generating a reconstructed version of a filesystem entity, the method may include (i) generating fallback retrieval metadata for a reconstructed version segment, when the reconstructed version segment is (a) associated with a corresponding intermediate version segment, and (b) the corresponding intermediate version segment is preceded by a corresponding most updated segment that does not exceed a fallback version of the filesystem entity; wherein the reconstructed version segment, the corresponding intermediate version segment and the corresponding most updated segment that does not exceed a fallback version have a same address range; (ii) generating a non-existing indicator for the reconstructed version segment, when the reconstructed version segment is (a) associated with the corresponding intermediate version segment, and (b) the corresponding intermediate version segment is not preceded by any corresponding most updated segment that does not exceed the fallback version; and (iii) maintaining intermediate metadata for retrieving one or more intermediate versions of the filesystem entity.

Reverting to a previous version of a filesystem entity

An apparatus comprises a source system comprising a distribution layer, a management component and a plurality of replication components. The distribution layer is configured to obtain an input-output operation corresponding to an address and to identify a given replication component that corresponds to the address based at least in part on a distribution instance. The distribution layer is configured to assign a first distribution identifier corresponding to the distribution instance to the input-output operation and to provide the input-output operation to the given replication component with the first distribution identifier. The given replication component is configured to obtain a second distribution identifier from the management component and to determine whether or not the first distribution identifier is equal to the second distribution identifier. The given replication component is further configured to perform at least one action on the obtained input-output operation based at least in part on the determination.

Maintaining replication consistency during distribution instance changes

Systems and methods for scalable locking. A method includes adding a first lock entry representing a pending lock to a first tree, the first lock entry indicating a range to be locked; checking at least a portion of at least one second tree to determine whether a conflicting lock exists for the first lock entry among at least one second lock entry based on the range to be locked, wherein each of the first tree and the at least one second tree is a data structure including a plurality of nodes representing at least a plurality of attributes, wherein the plurality of attributes of the at least one second tree includes the at least one second lock entry; committing the pending lock when no conflicting lock exists; and resolving the pending lock based on a resolution of the conflicting lock when a conflicting lock exists.

Growing community of inventors

Haifa, Israel

Oren Ashkenazi