Abstract: Techniques are disclosed for storage resource resynchronization using pending IO requests.

Abstract: Techniques can include: performing asynchronous replication for a source storage object and a target storage object; tracking writes tagged with a tracking identifier associated with a replication related snapshot of the source storage object; receiving a request at a source system to create identical user snapshots of the source storage object and the target storage object; creating a user snapshot of the source storage object; and storing a record in metadata of tracked writes denoting a time order of the request relative to tracked writes tagged with the tracking identifier; determining, in accordance with said tracking, first tracked writes tagged with the tracking identifier that are received before the request; replicating, to the target system, data changes from the replication related snapshot corresponding to the first tracked writes; and creating a user snapshot of the target storage object after data changes are applied to the target storage object.

Abstract: Techniques can include: configuring source sites in a replication configuration with a target site; receiving, at a first of the source sites from a host, a write I/O to a target location of a source storage object of the source site; sending a replicated write corresponding to the write I/O from the first source site to the target site, wherein the replicated write writes to the target location of a target storage object of the target site; prioritizing the replicated write, based at least in part, on a site-level priority associated with the first source site; placing the first replicated write in a first queue of a first plurality of queues based, at least in part, on the site level priority associated with the first source site; selecting the first replicated write from said first queue; and servicing the first replicated write.

Abstract: Techniques can include: configuring source sites in a replication configuration with a target site; receiving, at a first of the source sites from a host, a write I/O to a target location of a source storage object of the source site; sending a replicated write corresponding to the write I/O from the first source site to the target site, wherein the replicated write writes to the target location of a target storage object of the target site; prioritizing the replicated write, based at least in part, on a site-level priority associated with the first source site; placing the first replicated write in a first queue of a first plurality of queues based, at least in part, on the site level priority associated with the first source site; selecting the first replicated write from said first queue; and servicing the first replicated write.

Abstract: Techniques can include: receiving from a component a bufferless read request to read data of a storage object; opening a first transaction; acquiring locks of data pages including the read data; locking cache pages; storing the read data in the cache pages; sending to the component a notification identifying references, pointers or addresses of the cache pages storing the read data; responsive to receiving the notification, the first component performing one or more operations including directly accessing the first data from the cache pages using the references, pointers or addresses; and responsive to successfully completing the one or more operations, performing second processing including: releasing or unlocking the set of one or more cache pages storing the first data; releasing the one or more locks of the one or more data pages including the first data; and closing the first transaction.

Abstract: Techniques for resynchronizing storage resources of two sites configured for synchronous replication can include tracking in-progress write requests in a map. Responsive to a site failure or a replication link failure resulting in failure or fracture of the synchronous replication, processing can be performed to resynchronize impacted resources of the two sites configured for synchronous replication. The processing can use the in-progress write requests in combination with resource snapshots and snapshot differences to resynchronize the impacted resource of the two sites. In at least one embodiment, the synchronous replication configuration can include active paths between both sites and a host. In at least one embodiment, the synchronous replication configuration can include an active path between the host and one site, and a passive path between the host and the second site. The synchronous replication can be bi-directional or two-way synchronous replication between the two sites.

Abstract: Techniques for resynchronizing storage resources of two sites configured for synchronous replication can include tracking in-progress write requests in a map. Responsive to a site failure or a replication link failure resulting in failure or fracture of the synchronous replication, processing can be performed to resynchronize impacted resources of the two sites configured for synchronous replication. The processing can use the in-progress write requests in combination with resource snapshots and snapshot differences to resynchronize the impacted resource of the two sites. In at least one embodiment, the synchronous replication configuration can include active paths between both sites and a host. In at least one embodiment, the synchronous replication configuration can include an active path between the host and one site, and a passive path between the host and the second site. The synchronous replication can be bi-directional or two-way synchronous replication between the two sites.

Abstract: Techniques for resynchronizing storage resources of two sites configured for synchronous replication can include tracking in-progress write requests in a map. Responsive to a site failure or a replication link failure resulting in failure or fracture of the synchronous replication, processing can be performed to resynchronize impacted resources of the two sites configured for synchronous replication. The processing can use the in-progress write requests in combination with resource snapshots and snapshot differences to resynchronize the impacted resource of the two sites. In at least one embodiment, the synchronous replication configuration can include active paths between both sites and a host. In at least one embodiment, the synchronous replication configuration can include an active path between the host and one site, and a passive path between the host and the second site. The synchronous replication can be bidirectional or two-way synchronous replication between the two sites.

Abstract: Techniques are disclosed for storage resource resynchronization using pending IO requests.

Abstract: A method, computer program product, and computing system for determining a recovery point object (RPO) value for a storage object. An amount of data to transfer from the storage object to a disaster recovery site is determined. A data replication transfer schedule for the storage object is generated based upon, at least in part, the RPO value and the amount of data to transfer. Data is asynchronously transferred from the storage object to the disaster recovery site using the data replication transfer schedule.

Abstract: Techniques for creating identical snapshots can include: performing synchronous replication between a first storage object of a first system and a second storage object of a second system; enabling change tracking for the first storage object that records in a log which portions of the first storage object are written or modified; responsive to enabling change tracking, creating a snapshot S2 of the second storage object of the second system; responsive to creating the snapshot S2 of the second storage object; creating a snapshot S1 of the first storage object of the first system; responsive to creating the snapshot S1 of the first storage object, disabling change tracking for the first storage object; and copying written or modified content of the first storage object as identified in the log to the snapshot S2 of the second storage object of the second system.

Abstract: Techniques for creating identical snapshots can include: performing synchronous replication between a first storage object of a first system and a second storage object of a second system; enabling change tracking for the first storage object that records in a log which portions of the first storage object are written or modified; responsive to enabling change tracking, creating a snapshot S2 of the second storage object of the second system; responsive to creating the snapshot S2 of the second storage object; creating a snapshot S1 of the first storage object of the first system; responsive to creating the snapshot S1 of the first storage object, disabling change tracking for the first storage object; and copying written or modified content of the first storage object as identified in the log to the snapshot S2 of the second storage object of the second system.

Abstract: A data path connection can be established between a target of a remote source system and an initiator of a local destination system. A storage object of the remote source system exposed over such a data path connection can be mapped to a local storage object name of the local destination system. Such a remote storage object of the remote source system can be accessed as a local storage object of the local destination system using the local storage object name. Within the destination system, the local storage object name of the destination system can be used as a proxy to access the remote storage object of the remote source system. Accessing the remote storage object from the destination system can be used in several data mobility use cases, including, but not limited to, offloaded data copy across arrays, snapshot mobility and backup use-cases.

Abstract: A data path connection can be established between a target of a remote source system and an initiator of a local destination system. A storage object of the remote source system exposed over such a data path connection can be mapped to a local storage object name of the local destination system. Such a remote storage object of the remote source system can be accessed as a local storage object of the local destination system using the local storage object name. Within the destination system, the local storage object name of the destination system can be used as a proxy to access the remote storage object of the remote source system. Accessing the remote storage object from the destination system can be used in several data mobility use cases, including, but not limited to, offloaded data copy across arrays, snapshot mobility and backup use-cases.

Abstract: Techniques for creating and using snapshots may include: receiving a request to create a new snapshot of a source object; determining whether a first generation identifier associated with the source object matches a second generation identifier associated with a base snapshot of the source object; determining whether the source object has been modified since the base snapshot was created; and responsive to determining the first generation identifier matches the second generation identifier and also determining that the source object has not been modified since the base snapshot was created, associating the new snapshot with the base snapshot thereby indicating that the new snapshot and the base snapshot have matching content and denote a same point in time copy of the source object.

Abstract: A method, computer program product, and computer system for triggering, by a computing device, a synchronization activity on a storage object. A request may be executed for a copy operation resulting from the synchronization activity to copy the storage object from a source to a destination when a current number of concurrent copy operations is below a maximum number of copy operations. The request for the copy operation resulting from the synchronization activity to copy the storage object from the source to the destination may be placed in a queue when the current number of concurrent copy operations is at least at the maximum number of copy operations. One or more attributes of the request in the queue may be identified. The request for the copy operation may be executed according to a replication policy based upon, at least in part, the one or more attributes of the request in the queue.

Abstract: A method, computer program product, and computing system for receiving a plurality of discrete write requests on a first computing device until the end of a consolidation window; combining the plurality of discrete write requests received into a consolidated write request; and transmitting the consolidated write request to a second computing device.

Abstract: A method, computer program product, and computing system for receiving a plurality of discrete write requests on a first computing device until the end of a consolidation window; combining the plurality of discrete write requests received into a consolidated write request; and transmitting the consolidated write request to a second computing device.

Abstract: Techniques for creating and using snapshots may include: receiving a request to create a new snapshot of a source object; determining whether a first generation identifier associated with the source object matches a second generation identifier associated with a base snapshot of the source object; determining whether the source object has been modified since the base snapshot was created; and responsive to determining the first generation identifier matches the second generation identifier and also determining that the source object has not been modified since the base snapshot was created, associating the new snapshot with the base snapshot thereby indicating that the new snapshot and the base snapshot have matching content and denote a same point in time copy of the source object.

Abstract: A method, computer program product, and computer system for receiving, at a computing device, a write request from a host, wherein a first portion of a process may receive the write request. A callback and context may be set in the write request by the first portion of the process. The write request may be passed to a second portion of the process. The first process may be provided with the context. The first process may use the context to replicate the write request data to a destination.