摘要:
A method for providing rolling continuous data protection of source data is disclosed. In one embodiment, such a method includes enabling a user to select source data and establish a first interval when point-in-time copies of the source data are generated. The method further enables the user to specify a first number of point-in-time copies to retain at the first interval. The method further enables the user to specify a second number of point-in-time copies to retain at a second interval, wherein the second interval is a (n≧2) multiple of the first interval. The method further enables the user to specify a third number of point-in-time copies to retain at a third interval, wherein the third interval is a (n≧2) multiple of the second interval. A corresponding apparatus and computer program product are also disclosed.
摘要:
A method for allocating space in a cache based on media I/O speed is disclosed herein. In certain embodiments, such a method may include storing, in a read cache, cache entries associated with faster-responding storage devices and cache entries associated with slower-responding storage devices. The method may further include implementing an eviction policy in the read cache. This eviction policy may include demoting, from the read cache, the cache entries of faster-responding storage devices faster than the cache entries of slower-responding storage devices, all other variables being equal. In certain embodiments, the eviction policy may further include demoting, from the read cache, cache entries having a lower read-hit ratio faster than cache entries having a higher read-hit ratio, all other variables being equal. A corresponding computer program product and apparatus are also disclosed and claimed herein.
摘要:
A method for performing a write to a volume x in a cyclic point-in-time-copy architecture is described. In one embodiment, such a method includes determining whether the volume x has a child volume. The method then determines whether the target bit maps (TBMs) of both the volume x and the child volume are set. If the TBMs are set, the method finds a higher source (HS) volume from which to copy the desired data to the child volume. Once the HS volume is found, the method determines whether the HS volume and the child volume are the same volume. If the HS volume and the child volume are not the same volume, the method copies the data from the HS volume to the child volume. The method then performs the write to the volume x.
摘要:
A method, system, and computer program product for managing modified metadata in a storage controller cache pursuant to a recovery action by a processor in communication with a memory device is provided. A count of modified metadata tracks for a storage rank is compared against a predetermined criterion. If the predetermined criterion is met, a storage volume having the storage rank is designated with a metadata invalidation flag to defer metadata invalidation of the modified metadata tracks until after the recovery action is performed.
摘要:
A method is disclosed to locate a data storage device disposed in a data storage system. The method selects a target data storage device, identifies a target adapter port in communication with the target data storage device, and determines one or more target addresses, and determines one or more target World Wide Port Names (“WWPNs”). The method selects an enclosure, and a communication pathway disposed in that enclosure, and determines if any storage device ports interconnected with the communication pathway comprise a WWPN that matches any of said target WWPNs. If any storage device ports interconnected with the communication pathway comprise a WWPN that matches any of the target WWPNs, the method then identifies an adapter port in communication with that communication pathway, and determines if that any storage device ports in communication with the identified adapter port have claimed an address that matches a target address. If a storage device port in communication with the identified adapter port has claimed an address that matches a target address, then the method locates the target data storage device within the selected enclosure.
摘要:
A method for efficiently using a large secondary cache is disclosed herein. In certain embodiments, such a method may include accumulating, in a secondary cache, a plurality of data tracks. These data tracks may include modified data and/or unmodified data. The method may determine if a subset of the plurality of data tracks makes up a full stride. In the event the subset makes up a full stride, the method may destage the subset from the secondary cache. By destaging full strides, the method reduces the number of disk operations that are required to destage data from the secondary cache. A corresponding computer program product and apparatus are also disclosed and claimed herein.
摘要:
A method is disclosed to locate a data storage device disposed in a data storage system. The method selects a target data storage device, identifies a target adapter port in communication with the target data storage device, and determines one or more target addresses, and determines one or more target World Wide Port Names (“WWPNs”). The method selects an enclosure, and a communication pathway disposed in that enclosure, and determines if any storage device ports interconnected with the communication pathway comprise a WWPN that matches any of said target WWPNs. If any storage device ports interconnected with the communication pathway comprise a WWPN that matches any of the target WWPNs, the method then identifies an adapter port in communication with that communication pathway, and determines if that any storage device ports in communication with the identified adapter port have claimed an address that matches a target address. If a storage device port in communication with the identified adapter port has claimed an address that matches a target address, then the method locates the target data storage device within the selected enclosure.
摘要:
A method for efficiently using a large secondary cache is disclosed herein. In certain embodiments, such a method may include accumulating, in a secondary cache, a plurality of data tracks. These data tracks may include modified data and/or unmodified data. The method may determine if a subset of the plurality of data tracks makes up a full stride. In the event the subset makes up a full stride, the method may destage the subset from the secondary cache. By destaging full strides, the method reduces the number of disk operations that are required to destage data from the secondary cache. A corresponding computer program product and apparatus are also disclosed herein.