摘要:
Methods, system and computer program product are provided to improve the efficiency of data transfers in a PPRC environment. A block of data to be transferred is divided into tracks. Each track is allocated to a data mover task control block (TCB) with a master TCB being assigned to supervise the data mover TCBs. The tracks are then transferred from the primary storage controller to the secondary controller in a piped fashion over a link coupling the primary and secondary storage controllers. However, the usage of resources is monitored by a resource management algorithm and, if too many TCBs are being used for a transfer or if the supply of data mover TCBs is exhausted, the transfer is automatically switched to a serial, non-piped transfer with the master TCB serving as the data mover TCB for the remaining tracks. In addition, the various links coupling the primary and secondary storage controllers is monitored to determine which link will provide the fastest transfer. If, during a transfer of tracks over one link, a faster link is identified, the transfer may be switched to the second, faster link.
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:
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:
For a technique for maintaining consistency of data, one or more blocks of data identified by a first structure are copied to form a consistent set of data. While not acknowledging completion of write requests to any blocks of data, a second structure is created, wherein the second structure indicates which blocks of data are modified while the consistent set of data is being formed.
摘要:
A method for managing storage functions in a data replication environment is disclosed. In one embodiment, such a method includes continually monitoring for changes to a storage configuration at a secondary site. Upon detecting changes to the storage configuration at the secondary site, the method transmits remote metadata describing the changes to the primary site and stores the remote metadata at the primary site. The method then initiates a storage management function at the primary site which is mirrored to the secondary site. In order to perform the storage management function, the method reads the remote metadata at the primary site to determine the storage configuration at the secondary site. The method then performs the storage management function at the primary site in a way that takes into account the storage configuration at the secondary site. A corresponding apparatus, system, and computer-readable medium are also disclosed and claimed herein.
摘要:
A method is disclosed to write data to an information storage and retrieval system comprising (n) volumes and a data cache, where that information storage and retrieval system is capable of communicating with one or more host computers. The method receives from a host computer an update for the (i)th volume, and determines the (i)th delay, where that (i)th delay is associated with the (i)th volume. The method then writes the update to said data cache interposing the (i)th delay without indicating to said host computer that the information storage and retrieval system is unavailable.
摘要:
Provided are a method, 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:
Disclosed is a technique for applying changes back to an original copy of data to reduce an amount of data transferred. A first indicator is maintained for each block of data in a first storage to indicate whether the block of data has been updated in the first storage since the block of data was last transferred to a second storage. A second indicator is maintained for each block of data in the second storage to indicate whether the block of data has been updated in the second storage since the block of data in the second storage was overwritten by a corresponding block of data in the first storage. Upon receiving a reverse restore operation, each block of data in the second storage for which a second indicator has been set to indicate that the block of data has been updated is transferred to the first storage and each block of data in the second storage that corresponds to a block of data in the first storage for which a first indicator has been set to indicate that the block of data in the first storage has been updated is transferred to the first storage.
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:
A primary storage controller is configured to communicate with a secondary storage controller via a system data mover. In response to receiving a command to perform a point in time copy of a source volume of the primary storage controller to a target volume of the primary storage controller, a determination is made as to whether the target volume of the primary storage controller is a source for an asynchronous data replication operation, initiated by the system data mover, between the primary storage controller and the secondary storage controller. In response to determining that the target volume of the primary storage controller is the source for the asynchronous data replication operation, initiated by the system data mover, the point in time copy of the source volume of the primary storage controller to the target volume of the primary storage controller is performed.