摘要:
Disclosed is a technique for reducing an amount of data transferred. A first indicator is maintained for each source block of data to indicate whether the source block of data has been updated in source storage since the source block of data was last transferred to target storage. A second indicator is maintained for each target block of data in target storage to indicate whether the target block of data has been updated in target storage since the target block of data was overwritten by a corresponding source block of data. When transferring data from the source storage to the target storage, each source block of data for which a first indicator has been set to indicate that the source block of data has been updated is transferred and each source block of data that corresponds to a target block of data for which a second indicator has been set to indicate that the target block of data has been updated is transferred.
摘要:
Provided are a system and article of manufacture for copying storage. Copy operations are performed on source storage units to copy to target storage units, wherein the copy operations create a consistent copy of the source storage units in the target storage units. While performing a copy operation to copy from one source storage unit to one target storage unit, a write operation is restricted from being performed on the one source storage unit, until the copy operations have been performed on the source storage units.
摘要:
Provided are a method, system, and program for forming a consistency group of data. Information is provided on a consistency group relationship indicating a plurality of slave controllers and, for each indicated slave controller, a slave storage unit managed by the slave controller. A command is transmitted to each slave controller in the consistency group relationship to cause each slave controller to transmit data in the slave storage unit to a remote storage in a manner that forms the consistency group. A determination is made as to whether all the slave controllers successfully transmitted the data in the slave storage units that is part of the consistency group to the remote storage.
摘要:
Provided are a system and article of manufacture for copying storage. Copy operations are performed on source storage units to copy to target storage units, wherein the copy operations create a consistent copy of the source storage units in the target storage units. While performing a copy operation to copy from one source storage unit to one target storage unit, a write operation is restricted from being performed on the one source storage unit, until the copy operations have been performed on the source storage units.
摘要:
Provided is a method for copying storage. Copy operations are performed on source storage units to copy to target storage units, wherein the copy operations create a consistent copy of the source storage units in the target storage units. While performing a copy operation to copy from one source storage unit to one target storage unit, a write operation is restricted from being performed on the one source storage unit, until the copy operations have been performed on the source storage units.
摘要:
Techniques are provided for performing a copy operation. An instant virtual copy operation is issued from a first portion of data to a primary mirroring portion of data, wherein the primary mirroring portion of data corresponds to a secondary mirroring portion of data, and wherein the primary mirroring portion of data and the secondary mirroring portion of data are in a mirroring relationship. The mirroring relationship is transitioned to a duplex pending state in response to determining that the mirroring relationship is in a full duplex state. When the mirroring relationship is in a duplex pending state, each block of data involved in the instant virtual copy operation is transferred from the primary mirroring portion of data to the secondary mirroring portion of data.
摘要:
Provided are a method, system, and article of manufacture for copying storage. Data sent from a first storage unit is synchronously copied at a second storage unit. The copied data is sent asynchronously from the second storage unit to a third storage unit.
摘要:
A method and system for updating status information in a persistent storage. The method comprises the steps of defining a table in persistent storage (NVS) for holding information about changes to the status information; and when that status information is changed, making an entry in the table to record the changed information. A task is initialized to update the information on the disk drive. This updating is done by (i) checking the table to determine if any changes have been recorded in the persistent storage, and (ii) if any changes have been recorded in the persistent storage, then copying the status information from the persistent storage to the disk drive.
摘要:
Provided are a method, system, and program for managing data. A data request is received to a target track in a relationship, wherein the relationship associates a source track with the target track. A destage request to destage the source track is submitted in response to the data request to the target track, wherein executing the data request to the target track is conditioned on receiving a completion response to the destage request. If the source track is not in cache, then a complete response is returned to the destage request. If the source track was in cache when the relationship was established, then the destage request is added to an Input/Output (I/O) queue for the source track. After the source track is destaged in response to processing the destage request in the I/O queue, the complete response is returned to the destage request.
摘要:
Provided are a method, system, and program for managing resources in which a local processor sends remote operation requests to be executed by a remote processor having multiple resources. In the illustrated embodiment, the local processor and the remote processor each have a resource manager, each of which maintains a control set for each resource of the remote processor. Each control set of the remote processor resource manager includes a queue for queuing remote operation requests awaiting execution in connection with the resource associated with the control set. Each control set of the local processor resource manager includes a credit counter which keeps track of permissible outstanding remote operation requests. Each local processor control set credit counter is decremented for each remote operation request for the associated resource sent to the remote processor and is incremented for each acknowledgment received from the remote processor. For each remote processor control set, the remote processor resource manager sends an acknowledgment for each remote operation request initiated in connection with the associated resource. For each local processor control set, the local processor resource manager queues remote operation requests if the control set credit counter falls below a threshold after being initialized in accordance with the capacity of the associated remote processor control set queue.