摘要:
A method for synchronizing data storage systems is provided. The method comprises designating a relationship between a first data storage system and a second data storage system, such that data stored in the first data storage system is copied to the second data storage system, in response to determining that the data stored in the first data storage system has been modified; receiving a first request to modify data stored in a first data block of a first storage volume in the first data storage system, wherein the data block is modified according to the first request; determining that the first data block has not been successfully synchronized when the modified data stored in the first data block is not copied to the second data storage system; and executing a process to retry synchronization of the first data block until synchronization of the first data block is successful, without suspending the relationship while the process is executed.
摘要:
A method for synchronizing data storage systems is provided. The method comprises designating a relationship between a first data storage system and a second data storage system, such that data stored in the first data storage system is copied to the second data storage system, in response to determining that the data stored in the first data storage system has been modified; receiving a first request to modify data stored in a first data block of a first storage volume in the first data storage system, wherein the data block is modified according to the first request; determining that the first data block has not been successfully synchronized when the modified data stored in the first data block is not copied to the second data storage system; and executing a process to retry synchronization of the first data block until synchronization of the first data block is successful, without suspending the relationship while the process is executed.
摘要:
Disclosed is 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. Also disclosed is a technique for asynchronous copy. Indicators are updated in a first structure for one or more blocks of data, wherein each indicator in the first structure indicates whether a corresponding block of data was modified since the block of data was last sent to remote storage. While copying the blocks of data identified by the indicators in the first structure as having been modified since the blocks of data were last sent to remote storage, indicators in a second structure are updated for the one or more blocks of data, wherein each indicator in the second structure indicates whether a corresponding block of data was modified while a consistent set of data is being formed.
摘要:
Disclosed is a method, system, and program for managing metadata in cache. A first policy is used to determine when to remove data from a primary cache, and a second policy is used to determine when to remove data from a metadata cache.
摘要:
Provided are a method, system, and program for accessing a resource. Requests are generated to access a resource in a first access mode and a second access mode. The requests are processed to access the resource in the second mode before processing at least one request to access the resource in the first access mode. The processing of the requests to access the resource in the first access mode is delayed for a time period after processing all the requests to access the resource in the second access mode in order to wait to receive a subsequent request to access the resource in the second access mode.
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 mechanism is provided for managing operations in a data storage system. A first storage controller monitors operation state information associated with a plurality of operation states stored in a data structure. The first storage controller detects a change in the operation state information. The change in the operation state information is in response to a managing entity updating the operation state information to a first operation state in the plurality of operation states in the data structure. Responsive to detecting the change in the operation state information, the first storage controller identifies a reference to a first operation associated with the first operation state updated by the managing entity. The first operation is one operation in a plurality of operations. The first storage controller performs the first operation associated with the first operation state.
摘要:
Disclosed is a method, system, and program for managing metadata in cache. A first policy is used to determine when to remove data from a primary cache, and a second policy is used to determine when to remove data from a metadata cache.
摘要:
Disclosed is a method, system, and program for reducing an mount of data transferred. Indicators of sub-blocks modified for a block of data since the block of data was last sent to remote storage are maintained until the block of data is demoted. The maintained indicators are used to identify sub-blocks on the block of data for transfer to the remote storage.Disclosed is a method, system, and program for managing metadata in cache. A first policy is used to determine when to remove data from a primary cache, and a second policy is used to determine when to remove data from a metadata cache.
摘要:
Provided are a method, system, and article of manufacture for managing writes received to data units that are being transferred to a secondary storage as part of a mirror relationship. Synchronization information indicates data units to transfer from a primary storage to a secondary storage, wherein the synchronization information data is updated to indicate the transfer of one of the data units from the primary storage to the secondary storage. A storage controller receives a write request having an update to a target data unit comprising one of the data units indicated in the synchronization information that has not been transferred from the primary storage to the secondary storage. The write request is allowed to apply the update to the target data unit in response to transferring the data in the target data unit to a network adapter of the storage controller and before the data in the target data unit is transferred to the secondary storage.