Abstract: In asynchronous remote replication, write IOs are accumulated in capture cycles and sent to a remote storage system in transmit cycles. In order to cause metadata cache hits at the remote storage system, write IO data and associated metadata hints such as logical block addresses being updated are sent in successive cycles. The metadata hints, which are received at the remote storage system before the corresponding write IO data, are used to prefetch metadata associated with the logical block addresses being updated to replicate the write IO.

Abstract: Ransomware activity detection and data protection is implemented by a remote R2 storage array on an asynchronous remote data replication facility, on which data from a primary R1 storage array is replicated to the remote storage array. Write operations on storage volumes in a remote data replication group are collected in a capture cycle on the primary storage array, along with IO pattern metadata describing both read and write operations on the storage volumes. At the end of the capture cycle, the update and metadata is transmitted to the remote storage array. The remote storage array receives the update and metadata and temporarily stores the update prior to applying it to its copy of the storage volumes. Ransomware anomaly detection is implemented using the update and metadata, and if ransomware activity is detected, the data on the remote R2 storage array is protected, and the update is not applied.

Abstract: Selective packing of small block write operations is implemented prior to compression, to improve compression efficiency and hence reduce bandwidth requirements of a Remote Data Replication (RDR) facility. Compression characteristics of write IO operations are forecast, and write IO operations with similar forecast compression characteristics are pooled. Write IO operations are also grouped according to extent, device, and storage group. Write operations from a given compression pool are then preferentially selected from the extent-level grouping, next from the device-level grouping, and then from the SG-level grouping, to create an IO package. The IO package is then compressed and transmitted on the RDR facility. By creating an IO package prior to compression, it is possible to achieve greater compression than would be possible if each individual write IO operation were to be individually compressed to thereby reduce network bandwidth of the RDR facility.

Abstract: One or more aspects of the present disclosure relate to performant destaging of write pending (WP) data to disk. In embodiments, an input/output (IO) workload is received at a storage array. Additionally, the IO workload can include an IO request with a random write request. Further, a write destage context for write-pending (WP) data corresponding to the random write request can be generated by a data services engine of the storage array. In addition, using the write destage context, a disk adapter (DA), at a backend of the storage array, is enabled to destage write-pending (WP) data without reading from a target write location of the random write request on a storage device on the storage array.

Abstract: One or more aspects of the present disclosure relate to maximizing data migration bandwidth. In embodiments, one or more network characteristics corresponding to network communications between a first storage array and a second storage array is determined. Further, one or more network metrics of at least one acknowledgment communication from the second storage array to the first storage array can be analyzed. Additionally, one or more input/output (IO) messages are transmitted from the first storage array to the local storage array during an acknowledgment period corresponding to receipt of the at least one acknowledgment communication from the second storage array by the first storage array based on the one or more network metrics.

Abstract: A remote data replication facility includes a primary storage array and a backup storage array, on which tracks of data are replicated from the primary storage array to the backup storage array as they are received by the primary storage array. Remote data verification is implemented on the remote data replication facility by comparing track fingerprints, track temporal write metadata, and track spatial write metadata, for a given track on the primary storage array, with corresponding track fingerprints, track temporal write metadata, and track spatial write metadata, for the given track on the backup storage array. If any difference is determined in the combination of track fingerprints, track temporal write metadata, track spatial write metadata, for a given track, the integrity of the data at the backup storage array is not verified for the track.

Abstract: An example methodology includes provisioning memory of a storage array with cache memory including a plurality of cache slots and reading data from the memory of the storage array into a first cache slot of the plurality of cache slots, wherein the data in the first cache slot is in a first data format, the first data format being the format of data in the memory of the storage array. The method also includes converting the data in the first cache to a second data format distinct from the first data format and placing the data in the second data format into a second cache slot of the plurality of cache slots.

Abstract: One or more aspects of the present disclosure relate to performant destaging of write pending (WP) data to disk. In embodiments, an input/output (IO) workload is received at a storage array. Additionally, the IO workload can include an IO request with a random write request. Further, a write destage context for write-pending (WP) data corresponding to the random write request can be generated by a data services engine of the storage array. In addition, using the write destage context, a disk adapter (DA), at a backend of the storage array, is enabled to destage write-pending (WP) data without reading from a target write location of the random write request on a storage device on the storage array.

Abstract: Host IO write operations on a given storage group are grouped into cycles of a write destage pipeline for the storage group. Host writes are collected during a capture cycle, while host writes from a previous capture cycle are analyzed and destaged during an apply cycle. After the previous apply cycle has completed, a cycle switch occurs and the current capture cycle becomes the new apply cycle. Anomaly detection is implemented before any IO write operations are destaged during the apply cycle, and if an anomaly is detected the write destage is stopped. The entire apply cycle is either destaged to disk, or is discarded, depending on whether the anomaly is confirmed. By maintaining the order of writes across different cycles, which act as consistency points, it is possible to implement ransomware protection in real time on host write operations, while using ordered write destage to maintain data consistency.

Abstract: Ransomware activity detection and data protection is implemented by a remote R2 storage array on an asynchronous remote data replication facility, on which data from a primary R1 storage array is replicated to the remote storage array. Write operations on storage volumes in a remote data replication group are collected in a capture cycle on the primary storage array, along with IO pattern metadata describing both read and write operations on the storage volumes. At the end of the capture cycle, the update and metadata is transmitted to the remote storage array. The remote storage array receives the update and metadata and temporarily stores the update prior to applying it to its copy of the storage volumes. Ransomware anomaly detection is implemented using the update and metadata, and if ransomware activity is detected, the data on the remote R2 storage array is protected, and the update is not applied.

Abstract: The present disclosure relates to applying a data deduplication layer on top of an asynchronous remote replication protocol. In embodiments, a remote replication group including one or more of a storage array's logical unit numbers (LUNs) can be established. Further, at a remote system, —the remote replication group can be remotely replicated on a per LUN basis using a deduplication fingerprint of each LUN's data tracks corresponding to the remote replication group.

Abstract: The present disclosure relates to applying a data deduplication layer on top of an asynchronous remote replication protocol. In embodiments, a remote replication group including one or more of a storage array's logical unit numbers (LUNs) can be established. Further, at a remote system, —the remote replication group can be remotely replicated on a per LUN basis using a deduplication fingerprint of each LUN's data tracks corresponding to the remote replication group.

Abstract: The meta data containing count and key fields of CKD records are reversibly decoupled from the user data of the data field so that the data can be deduplicated. Multiple CKD records may be coalesced into a larger size CKD track. The coalesced meta data is compressed and stored in a CKD hash table. The user data is hashed, and the hash is used as a hash key that is associated with the compressed meta data in the CKD hash table. When the hash of user data associated with a CKD write IO matches the hash key of an existing entry in the table, data duplication is indicated. The compressed meta data is added to the entry and the user data is deduplicated by creating storage system meta data that points to the pre-existing copy of the user data. The storage system metadata includes unique information that enables the corresponding compressed metadata to be subsequently located in the hash table to reassemble the CKD records.

Abstract: The meta data containing count and key fields of CKD records are reversibly decoupled from the user data of the data field so that the data can be deduplicated. Multiple CKD records may be coalesced into a larger size CKD track. The coalesced meta data is compressed and stored in a CKD hash table. The user data is hashed, and the hash is used as a hash key that is associated with the compressed meta data in the CKD hash table. When the hash of user data associated with a CKD write IO matches the hash key of an existing entry in the table, data duplication is indicated. The compressed meta data is added to the entry and the user data is deduplicated by creating storage system meta data that points to the pre-existing copy of the user data. The storage system metadata includes unique information that enables the corresponding compressed metadata to be subsequently located in the hash table to reassemble the CKD records.

Abstract: Embodiments of the present disclosure relate to throttling processing threads of a storage device. One or more input/output (I/O) workloads of a storage device can be monitored. One or more resources consumed by each thread of each storage device component to process each operation included in a workload can be analyzed. Based on the analysis, consumption of each resource consumed by each thread can be controlled.

Abstract: A synchronous destage process is used to move data from shared global memory to back-end storage resources. The synchronous destage process is implemented using a client-server model between a data service layer (client) and back-end disk array of a storage system (server). The data service layer initiates a synchronous destage operation by requesting that the back-end disk array move data from one or more slots of global memory to back-end storage resources. The back-end disk array services the request and notifies the data service layer of the status of the destage operation, e.g. a destage success or destage failure. If the destage operation is a success, the data service layer updates metadata to identify the location of the data on back-end storage resources. If the destage operation is not successful, the data service layer re-initiates the destage process by issuing a subsequent destage request to the back-end disk array.

Abstract: A synchronous destage process is used to move data from shared global memory to back-end storage resources. The synchronous destage process is implemented using a client-server model between a data service layer (client) and back-end disk array of a storage system (server). The data service layer initiates a synchronous destage operation by requesting that the back-end disk array move data from one or more slots of global memory to back-end storage resources. The back-end disk array services the request and notifies the data service layer of the status of the destage operation, e.g. a destage success or destage failure. If the destage operation is a success, the data service layer updates metadata to identify the location of the data on back-end storage resources. If the destage operation is not successful, the data service layer re-initiates the destage process by issuing a subsequent destage request to the back-end disk array.

Abstract: Embodiments of the present disclosure relate to throttling processing threads of a storage device. One or more input/output (I/O) workloads of a storage device can be monitored. One or more resources consumed by each thread of each storage device component to process each operation included in a workload can be analyzed. Based on the analysis, consumption of each resource consumed by each thread can be controlled.

Abstract: In a data storage system in which a first storage array and a second storage array maintain first and second replicas of a production volume, the replicas are made discoverable and accessible while inconsistent. Each storage array maintains an invalid track list of inconsistencies. Initially, all tracks are marked as invalid. While background synchronization is eliminating inconsistencies, accesses to invalid tracks are resolved by exchanging data associated with IOs and updating the invalid track lists based on IO bias and other factors.

Abstract: In a data storage system in which a first storage array and a second storage array maintain first and second replicas of a production volume, the replicas are made discoverable and accessible while inconsistent. Each storage array maintains an invalid track list of inconsistencies. Initially, all tracks are marked as invalid. While background synchronization is eliminating inconsistencies, accesses to invalid tracks are resolved by exchanging data associated with IOs and updating the invalid track lists based on IO bias and other factors.