Abstract: A method for optimizing cleaning of maps in FlashCopy cascades includes determining whether a target disk of a map contains data unavailable to a downstream disk from an upstream disk in a FlashCopy cascade and detect whether the downstream disk has a copy of the data. Additionally, the method includes copying the data from the target disk to the downstream disk, if the target disk of the map contains data unavailable to the downstream disk from the upstream disk and the downstream disk does not have the copy of the data. Furthermore, the method includes copying the data from the target disk to the downstream disk, if the target disk of the map does not contain data unavailable to the downstream disk from the upstream disk or the downstream disk does have the copy of the data. Moreover, the method includes removing the map from the FlashCopy cascade.

Abstract: A technique for handling a FlashCopy® process includes receiving a FlashCopy® instruction for a source disk, performing a FlashCopy® point in time copy of the source disk on to a target disk, creating a map specifying the FlashCopy® point in time copy from the source disk to the target disk, creating a primary fdisk for the source disk, if one does not already exist, and creating a primary fdisk for the target disk, if one does not already exist, or, if one does already exist, converting the existing primary fdisk for the target disk into a secondary fdisk, and creating a new primary fdisk for the target disk.

Abstract: A data storage system comprises a controller, a first lower performance storage medium and a second higher performance storage medium. The controller is connected to the storage mediums and is arranged to control Input/Output (IO) access to the storage mediums. In operation, the controller is arranged to store an image on the first storage medium, initiate a copy function from the first storage medium to the second storage medium, direct all IO access for the image to the second storage medium, and periodically age data from the second storage medium to the first storage medium.

Abstract: A targeting storage component selects a target virtual disk for one of a full copy or an incremental copy of first data. A periodic backup component triggers a periodic point-in-time copy of the first data to a virtual disk in the cascade. A testing component tests a status of the full copy, the incremental copy and the periodic point-in-time copy. Responsive to the status, a cascade splitting component splits the cascade to remove a dependency relationship of at least one of the fully copy, the incremental copy and the periodic point-in-time copy on the first data.

Abstract: A storage control apparatus in cooperation with a plurality of controlled storage apparatus arranged in a cascade of point-in-time copy relationship. The apparatus includes: a rate control component operable to set a desired rate for cleaning a first target one of the plurality of controlled storage apparatus; a comparator component in communication with the rate control component to identify discrepant bits associated with first and second targets; and a copy initiator, responsive to the comparator component to initiate a copy operation responsive to the identified discrepant bits.

Abstract: A method implemented in a computer infrastructure having computer executable code having programming instructions tangibly embodied on a computer readable storage medium. The programming instructions are operable to determine whether a target disk of a map contains data unavailable to a downstream disk from an upstream disk in a FlashCopy cascade and detect whether the downstream disk has a copy of the data. Additionally, the programming instructions are operable to copy the data from the target disk to the downstream disk, if the target disk of the map contains data unavailable to the downstream disk from the upstream disk and the downstream disk does not have the copy of the data. Furthermore, the programming instructions are operable to refrain from copying the data from the target disk to the downstream disk, if the target disk of the map does not contain data unavailable to the downstream disk from the upstream disk or the downstream disk does have the copy of the data.

Abstract: A storage control apparatus cooperable with a plurality of controlled storage apparatus arranged in a cascade of point-in-time copy relationship. The apparatus includes: a rate control component operable to set a desired rate for making clean a first target one of the plurality of controlled storage apparatus; a comparator component responsive to a signal from the rate control component to request and receive metadata from the plurality of controlled storage apparatus and to identify discrepant metadata; and a copy initiator, responsive to the comparator component to identify discrepant metadata and to initiate a copy operation from a first target one of the plurality of controlled storage apparatus to a second target one of the controlled storage apparatus.

Abstract: A controller for use at a node of a clustered computer apparatus includes an exception detection component for detecting an exception raised by a service component at the node; a quiesce component responsive to the exception detection component for quiescing lease-governed activity by the service component prior to termination of a lease; a lease control component responsive to the quiesce component for pre-expiry relinquishing of the lease; and a communication component responsive to the lease control component for communicating the pre-expiry relinquishing of the lease to one or more further nodes of the clustered computer apparatus. The controller may further include a second communication component for receiving a communication indicating the pre-expiry relinquishing of a lease; a second lease control component responsive to the communication to control failure processing; and a second service component to perform a service in place of the service component at the node.

Abstract: Managing resource reclamation in data storage systems is provided. A volume deletion metadata recorder records metadata for one or more deleted volumes. A policy engine, responsive to a predetermined policy rule, applies the policy rule to the metadata. The policy engine initiates policy-controlled data storage space reclamation for the one or more deleted volumes. A volume reclaimer, responsive to the policy engine, reclaims data storage space from the one or more deleted volumes. A resource allocator allocates the data storage space to satisfy a minimum requirement for available zeroed extents that comprise a minimum requirement to satisfy needs of late allocated storage volumes.

Abstract: Systems and methods to forward data frames are described. A particular method may include associating a fiber channel forwarder with a bridge element. The fiber channel forwarder may be one of a plurality of fiber channel forwarders coupled to the bridge element. A data frame received at the bridge element may be forwarded to the fiber channel forwarder.

Abstract: Systems and methods to forward data frames are described. A particular method may include evaluating header data of a data frame at a bridge element, where the header data includes address data that corresponds to a Fiber Channel Forwarder in communication with the bridge element. Based upon the evaluation, the header data of the data frame may be modified at the bridge element in such a manner that the data frame is not routed through the Fiber Channel Forwarder.

Abstract: Methods and systems for memory management. A method for memory management includes: maintaining a reference count for at least one first process associated with a portion of memory; maintaining a shared reference count for at least one second process associated with the portion of memory; and freeing the portion of memory when the shared reference count is decremented to zero.

Abstract: A technique for handling a FlashCopy® process includes receiving a FlashCopy® instruction for a source disk, performing a FlashCopy® point in time copy of the source disk on to a target disk, creating a map specifying the FlashCopy® point in time copy from the source disk to the target disk, creating a primary fdisk for the source disk, if one does not already exist, and creating a primary fdisk for the target disk, if one does not already exist, or, if one does already exist, converting the existing primary fdisk for the target disk into a secondary fdisk, and creating a new primary fdisk for the target disk.

Abstract: A backup control apparatus for periodic data backup, in a virtualized storage system having a point-in-time copy function operable to copy first data into a cascade, comprises a storage targeting component for selecting a target virtual disk for one of a full copy or an incremental copy of the first data; a periodic backup component for triggering a periodic point-in-time copy of the first data to a virtual disk in the cascade; a testing component for testing a status of the full copy, the incremental copy and the periodic point-in-time copy; and a cascade splitting component responsive to the status for splitting the cascade to remove a dependency relationship of at least one of the full copy, the incremental copy and the periodic point-in-time copy on the first data.

Abstract: A mechanism is provided in a computing system for controlling virtualized storage operable to communicate with a host and with mapped and unmapped storage resource pools. A selection component selects a target for a destructive data storage operation from the mapped storage resource pool. Responsive to the selection of the target, a virtual targeting component creates a virtual target from the unmapped storage resource pool to represent the target. Responsive to the selection of the target, a storage move component moves the target to a protected storage resource pool. Responsive to the creation of the virtual target from the unmapped storage resource pool, storage move component, moves the virtual target to the used storage resource pool. The computing system then performs the destructive data storage operation on the virtual target.

Abstract: A method, storage system, and machine-readable medium for resynchronizing data stored among a first storage element and a second storage element of a remote copy pair of storage elements is disclosed. According to one embodiment, a method is provided which includes detecting a reestablishment of a remote copy relationship between the first and second storage elements and performing a resynchronization operation in response to this detection. Performing the resynchronization operation comprises transmitting data of a second change record associated with the second storage element to the first storage element, combining the second change record with a first change record associated with the first storage element, identifying a data segment of the second storage element utilizing the combined change record, and overwriting data of the first storage element with data of the identified data segment.

Abstract: A method implemented in a computer infrastructure having computer executable code having programming instructions tangibly embodied on a computer readable storage medium. The programming instructions are operable to determine whether a target disk of a map contains data unavailable to a downstream disk from an upstream disk in a FlashCopy cascade and detect whether the downstream disk has a copy of the data. Additionally, the programming instructions are operable to copy the data from the target disk to the downstream disk, if the target disk of the map contains data unavailable to the downstream disk from the upstream disk and the downstream disk does not have the copy of the data. Furthermore, the programming instructions are operable to refrain from copying the data from the target disk to the downstream disk, if the target disk of the map does not contain data unavailable to the downstream disk from the upstream disk or the downstream disk does have the copy of the data.

Abstract: Managing resource reclamation in data storage systems is provided. A volume deletion metadata recorder records metadata for one or more deleted volumes. A policy engine, responsive to a predetermined policy rule, applies the policy rule to the metadata. The policy engine initiates policy-controlled data storage space reclamation for the one or more deleted volumes. A volume reclaimer, responsive to the policy engine, reclaims data storage space from the one or more deleted volumes. A resource allocator allocates the data storage space to satisfy a minimum requirement for available zeroed extents that comprise a minimum requirement to satisfy needs of late allocated storage volumes.

Abstract: An apparatus is disclosed in which a storage controller cooperable with a host and a plurality of controlled storage is provided to localize an impact of a failure to a target disk in an affected segment. The storage controller includes a host write component to write a data object to a source image storage; a first copy component responsive to a first metadata state to control copying of the data object to a first target storage; a second copy component responsive to a second metadata state to perform either: copying the data object to a second target or causing the first copy component to copy the second target to the first target; and a third copy component to control cascaded copying of the data object to a third target storage. Either the second or the third copy component controls cascaded copying of a delimited data image subsequence responsive to a metadata state indicating currency of a data grain in either the second or the third target.

Abstract: A storage unit adapted for use in a processing system, includes: a journal for managing execution of incomplete writing of data for at least two segments of data, wherein a designated storage location for the first write of data overlaps a least a portion of a designated storage location for the second write of data, wherein the journal includes a reference table for tracking incomplete writes of data; and, the journal includes machine executable instructions stored within machine readable media for performing the managing by: monitoring writes of data to identify incomplete writes of data sharing at least one designated storage location of a primary media; reading the associated writes of data into the reference table; sequencing the associated writes of data in the reference table; and writing the data in the reference table in sequence order to each designated storage location of the primary media and associated secondary media.