Abstract: An example method for a first host, being an owner of an object stored in a virtual storage area network (vSAN) cluster, to perform encryption and decryption operations during a rekey in the vSAN cluster is disclosed. The method includes obtaining a first encryption key and a first key identifier (ID) of the first encryption key; transmitting the first key ID and an active key index to a second host; using the first encryption key to perform encryption and decryption operations; and in response to a determination of receiving a key change notification from a master node of the vSAN cluster, terminating a connection with the second host.

Abstract: A method of managing storage space of a storage device, wherein the storage device includes a plurality of snapshots of a file, includes the steps of: in response to a request to delete a first snapshot, determining a first amount of time that elapsed between a creation of the first snapshot and a creation of a second snapshot that is a child snapshot of the first snapshot: and after determining the first amount of time, executing a first process to delete the first snapshot over a first time interval, wherein the first time interval is based on the first amount of time.

Abstract: A method for inline block-level deduplication is provided. The method generally includes receiving an input/output (I/O) to write a first data block in storage as associated with an logical block address (LBA), hashing the first data block to a first hash, determining a match for the first hash is contained in a bloom filter based on set bits in the bloom filter for the first hash, determining an entry for the first data block is contained in a deduplication hash table based on a subset of bits of the first hash, locating a first middle map extent in a middle map based on a middle block address (MBA) included in the entry, verifying the first hash matches the first hash stored in the middle map extent, adding a logical map extent for the LBA to a logical map, wherein the logical map extent maps the LBA to the MBA.

Abstract: Examples provide a method of communication between a client application and a filesystem server in a virtualized computing system. The client application executes in a virtual machine (VM) and the filesystem server executes in a hypervisor.

Abstract: A method for deleting one or more snapshots using micro-batch processing is provided. The method includes receiving a request to delete the one or more snapshots, identifying one or more middle map extents exclusively owned by the one or more snapshots requested to be deleted, wherein metadata for the one or more snapshots is stored in one or more logical maps having logical map extents mapping logical block addresses (LBAs) to middle block addresses (MBAs) and a middle map having middle map extents mapping MBAs to physical block addresses (PBAs) of physical locations where data blocks are written, adding MBAs of the identified one or more middle map extents in a batch, determining a first micro-batch including a first subset of the MBAs in the batch, the first subset of MBAs being MBAs less than a first upper bound MBA, and using a first transaction to delete the middle map extents corresponding to the first subset of MBAs included in the first micro-batch.

Abstract: A method for compressing is provided. The method including receiving a block of data to store on at least one physical disk; determining whether to store the data in a data log as uncompressed or compressed data based on a determined size of resulting compressed data. When the method determines to store the data as compressed, compressing the data and storing the compressed data in at least one sector in the data log. Otherwise, the method stores the data, uncompressed, in a plurality of sectors in the data log. The method generates a one or more state bits indicating (i) whether the data is stored as uncompressed or compressed, and (ii) if the data is stored as compressed, a size of the compressed data. The method then stores the one or more state bits in an entry of a logical map table associated with an LBA that corresponds to the data block.

Abstract: A method for resumeable snapshot deletion is provided. A method for deletion of nodes maintained in an ordered data structure for a first snapshot includes processing the nodes maintained in the ordered data structure according to a defined order, setting a node path cursor with a pointer to a node and an indication of the deletion of the node; storing the node path cursor in a persistent storage; and during processing of the nodes: detecting a failure; after the failure, checking the pointer of the node path cursor; and resuming processing of the nodes starting from the first node indicated by the pointer.

Abstract: A method for managing data associated with objects stored in a cloud storage is provided. The method receives, at a first compute node, first data associated with an object stored in the cloud storage, the first compute node being one of a plurality of compute nodes that store data associated with different objects as storage objects in a log-structured merging (LSM) tree data structure. The method then assigns a first unique name to a first storage object associated with the first data, the first unique name comprising a combination of at least an identifier identifying the first compute node and a first incremental local value. The method stores the first storage object in a first level (L0) of the LSM tree data structure.

Abstract: A method for copy on write (COW) operations generally includes receiving a write request to a first node in an ordered data structure and updating a write ahead log record associated with COW operation with, instead of the content of the first node, a physical disk address of a second node owned by the run point in the ordered data structure that is a parent node of the first node, a pointer to the first node in the second node, a physical disk address of the first node, and a physical disk address of the third node. A metadata table record for a snapshot that owns the first node may be updated with a log sequence number (LSN) of the COW operation. A method for deleting a snapshot includes determining whether the COW operation recorded in the WAL record for the LSN is completed before deleting the snapshot.

Abstract: Disclosed techniques include deduplication. Techniques include determining whether a file is unique, and depending on whether the file is unique, deduplicating only part of the file or the entire file. The techniques include processing the first chunk of a file to determine whether the hash of the chunk hash is already within a chunk hash table, and if not, then a percentage of chunks of the file is similarly processed. If any of the hashes of chunks are already in the chunk hash table, then at least some of file has been previously deduplicated, and file is not unique the storage system. If none of the processed chunks have a hash that is already in the chunk hash table, then the file is considered to be unique within chunk store and only a partial percentage of the file's chunks are deduplicated. Not all of a unique file's chunks are deduplicated.

Abstract: System and method for deleting parent snapshots of running points of storage objects stored in a storage system, in response to a request to delete a parent snapshot of a running point of a storage object stored in the storage system, changes the minimum extent ownership value of the running point to the minimum extent ownership value of the parent snapshot so that any physical extent with an extent ownership value equal to or greater than the changed minimum extent ownership value is deemed to be owned by the running point. For each logical block of the parent snapshot, depending on whether the physical extent corresponding to that logical block is determined to be exclusively accessible to the parent snapshot, the physical extent is removed or no action is taken on the physical extent so that the physical extent is used by the running point.

Abstract: A method for modifying key-value pairs of a B+ tree is provided. The method receives a request to modify a particular key-value pair. Each node of the tree has a modification number. The method traverses a path on the tree from the root node toward the particular node. The traversing includes upon reaching a parent node of the path, acquiring a shared lock on both the parent node and a child node one level below the parent node. Upon determining that the child node is the particular node, the method stores the modification number of the particular node, releases the shared lock on the particular node, compares a current modification number of the node with its stored number, and acquires an exclusive lock on the node if the numbers are the same. The method increments the current modification number of the node and modifies it while in the exclusive lock.

Abstract: In one set of embodiments, a computer system can create a snapshot of a data set, where the snapshot includes a plurality of data blocks of the data set. The computer system can upload the snapshot to a cloud object storage platform of a cloud infrastructure, where the snapshot is uploaded as a plurality of log segments conforming to an object format of the cloud object storage platform, and where each log segment includes one or more data blocks in the plurality of data blocks, and a set of metadata comprising, for each of the one or more data blocks, an identifier of the data set, an identifier of the snapshot, and a logical block address (LBA) of the data block. The computer system can then communicate the set of metadata to a server component running in a cloud compute and block storage platform of the cloud infrastructure.

Abstract: The application discloses a placement system for a door of a wafer pod, including a loadport. A docking interface is formed in the loadport, a placement mechanism is arranged on one side surface of the loadport, and includes a swing component, a follower component, and a docking plate. The swing component and the follower component are respectively connected to the docking plate, and the swing component can drive the docking plate to place the docking plate obliquely above the docking interface. By utilizing the space at the top of the loadport, the structural layout of the loadport is more reasonable; and the docking plate is placed nearly horizontally after the door is placed at a designated position, and provides a supporting force to the door, so that dependence on the vacuum suction is decreased, thereby avoiding the influences due to fluctuations of air pressure.

Abstract: A method for the reverse deletion of a plurality of snapshots in a chain of snapshots is provided. The method includes in reverse order, starting from a latest snapshot in time to an earliest snapshot in time of the plurality of snapshots: identifying at least one of a first set of one or more data blocks of a snapshot that are shared with an earlier snapshot in time in the chain of snapshots or a second set of one or more data blocks of the snapshot that are owned by the snapshot and processing the second set of one or more data blocks and skipping processing the first set of one or more data blocks, wherein processing the second set of one or more data blocks comprises performing one or more actions to maintain and/or delete data blocks of the second set of one or more data blocks.

Abstract: Example methods and systems for accessing data in a log-structured file system having a plurality of snapshots of storage objects backed by a first-level copy-on-write (COW) B+ tree data structure and a plurality of second-level B+ tree data structures have been disclosed. One example method includes obtaining a first first-level mapping associated with a first snapshot from the plurality of snapshots based on a first logical block address, wherein each of the plurality of snapshots corresponds to each of the plurality of second-level B+ tree data structures, identifying a first second-level B+ tree data structure corresponding to one of the plurality of snapshots based on the first first-level mapping, obtaining a first second-level mapping based on the first logical block address in the first second-level B+ tree data structure, obtaining a first physical block address based on the first second-level mapping, and accessing data at the first physical block address.

Abstract: Techniques for reducing data log recovery time and metadata write amplification when checkpointing a data log of a storage object in a distributed storage system are provided. In one set of embodiments, a node of the system can determine whether the data log has reached a first threshold size, where the data log comprises a plurality of data log records, and where each data log record includes data and metadata for a write request directed to the storage object. If the data log has reached the first threshold size, the node can copy, from each of the plurality of data log records, the metadata for the write request to a corresponding metadata log entry in a metadata log of the storage object. The node can then truncate the data log by removing the plurality of data log records.

Abstract: The present disclosure is related to methods, systems, and machine-readable media for managing extent sharing between snapshots using mapping addresses. A first mapping address can be assigned to a first extent responsive to a request to write the first extent. A second mapping address can be assigned to a second extent responsive to a request to write the second extent. A snapshot can be created. A snapshot mapping address, that is monotonically increased from the second mapping address, can be assigned to the snapshot. A third mapping address, that is monotonically increased from the second mapping address, can be assigned to a third extent of the snapshot responsive to a request to write the third extent.

Abstract: The disclosure herein describes writing data to a log-structured merge (LSM) tree file system on an object storage platform. Write data instructions indicating data for writing to the LSM tree file system are received. Based on the received instructions, the data is written to the first data cache. Based on an instruction to transfer data in the live data cache to the LSM tree file system, the first data cache is converted to a stable cache. A second data cache configured as a live data cache is then generated based on cloning the first data cache. The data in the first data cache is then written to the LSM tree file system. Use of a stable cache and a cloned live data cache enables parallel writing data to the file system by the stable cache and handling write data instructions by the live data cache.

Abstract: A method of managing storage space of a storage device containing a plurality of snapshots of a file includes the steps of: recording a first count record that includes a number of data blocks that are owned by a first snapshot; after recording the first count record, recording a second count record that includes a number of data blocks that are both owned by the first snapshot and shared with a second snapshot that is a child snapshot of the first snapshot; and determining an amount of reclaimable space of the first snapshot as the difference between the numbers of data blocks of the first and second count records.