Abstract: Provided are a computer program product, system, and method for establishing a point-in-time copy relationship between source logical addresses and target logical addresses. A point-in-time (PiT) copy establish command specifies a source set comprising a subset of source logical addresses in at least one storage and a target set comprising a subset of target logical addresses in the at least one storage. The source set of source logical addresses are copied to the target set of target logical addresses. The source logical addresses map to source tracks and wherein the target logical addresses map to target tracks. Copy information is generated indicating whether the source logical addresses in the source set have been copied to the target set. Complete is returned to the PiT copy establish command after generating the copy information and before copying all the source logical addresses to the target logical addresses.

Abstract: A storage controller receives a write command with respect to a track, from a host. A first process determines that the track is a source track and also determines that at least one corresponding target track is in an incremental copy relation to the source track. A second process is generated to modify a target change recording structure, where the second process executes in parallel with the first process.

Abstract: Provided are a computer program product, system, and method for assigning device adaptors to use to copy source extents in source ranks to target extents in target ranks in a copy relation. A determination is made of an order of the target ranks in the copy relation. Target ranks in the copy relation are selected according to the determined order. For each selected target rank, indication is made in a device adaptor assignment data structure of a source device adaptor and target device adaptor of the device adaptors to use to copy the source rank to the selected target rank indicated in the copy relation, wherein indication is made for the selected target ranks according to the determined order. The source ranks are copied to the selected target ranks using the source and target device adaptors indicated in the device adaptor assignment data structure.

Abstract: A method for improving system availability in data replication environments is disclosed herein. In one embodiment, such a method includes detecting a suspend trigger, where the suspend trigger indicates that data mirroring between a primary volume and a secondary volume has been suspended. The method further detects a swap trigger some time after detecting the suspend trigger. The swap trigger indicates that I/O directed to the primary volume has failed. In the event the swap trigger is detected within a specified amount of time after detecting the suspend trigger, the method redirects I/O from the primary volume to the secondary volume. A corresponding system and computer program product are also disclosed.

Abstract: A method for improving system availability in data replication environments is disclosed herein. In one embodiment, such a method includes detecting a suspend trigger, where the suspend trigger indicates that data mirroring between a primary volume and a secondary volume has been suspended. The method further detects a swap trigger some time after detecting the suspend trigger. The swap trigger indicates that I/O directed to the primary volume has failed. In the event the swap trigger is detected within a specified amount of time after detecting the suspend trigger, the method redirects I/O from the primary volume to the secondary volume. A corresponding system and computer program product are also disclosed.

Abstract: Provided are a computer program product, system, and method for asynchronous pausing of the formation of consistency groups. A first copy operation is initiated to copy the source data from the first storage to the first data copy in the second storage. A second copy operation is initiated to copy the first data copy in the second storage to a second data copy in response to forming a consistency group of the source data at the first data copy forms consistent as of a point-in-time with respect to the source data. The first copy operation is suspended to allow for further processing of the first data copy in response to completing the second copy operation. The formation of a next consistency group is restarted between the source data and the first data copy in response to receiving a resume command.

Abstract: Provided are techniques for local locking in a bi-directional synchronous mirroring environment. In response to receiving a write operation for a block of data on a first volume, a lock is obtained on a corresponding block of data on a second volume to obtain exclusive access to that block of data on the second volume. in response to determining that an active write indicator is set to indicate that there is not an active write on the second volume, updated data for the corresponding block of data is written to cache for the second volume, the lock is released to remove exclusive access to the corresponding block of data on the second volume, and a transfer complete message is sent to the first volume.

Abstract: A first data structure stores indications of storage locations that need to be copied for forming a consistency group. A second data structure stores indications of new host writes, subsequent to starting a point in time copy operation to form the consistency group. Locations of the first data structure and the second data structure are exchanged, subsequent to the consistency group being formed successfully.

Abstract: Provided are a computer program product, system, and method for establishing a point-in-time copy relationship between source logical addresses and target logical addresses. A point-in-time (PiT) copy establish command specifies a source set comprising a subset of source logical addresses in at least one storage and a target set comprising a subset of target logical addresses in the at least one storage. The source set of source logical addresses are copied to the target set of target logical addresses. The source logical addresses map to source tracks and wherein the target logical addresses map to target tracks. Copy information is generated indicating whether the source logical addresses in the source set have been copied to the target set. Complete is returned to the PiT copy establish command after generating the copy information and before copying all the source logical addresses to the target logical addresses.

Abstract: Provided are a computer program product, system, and method for asynchronous pausing of the formation of consistency groups. A first copy operation is initiated to copy the source data from the first storage to the first data copy in the second storage. A second copy operation is initiated to copy the first data copy in the second storage to a second data copy in response to forming a consistency group of the source data at the first data copy forms consistent as of a point-in-time with respect to the source data. The first copy operation is suspended to allow for further processing of the first data copy in response to completing the second copy operation. The formation of a next consistency group is restarted between the source data and the first data copy in response to receiving a resume command.

Abstract: Provided are a computer program product, system, and method for assigning device adaptors to use to copy source extents in source ranks to target extents in target ranks in a copy relation. A determination is made of an order of the target ranks in the copy relation. Target ranks in the copy relation are selected according to the determined order. For each selected target rank, indication is made in a device adaptor assignment data structure of a source device adaptor and target device adaptor of the device adaptors to use to copy the source rank to the selected target rank indicated in the copy relation, wherein indication is made for the selected target ranks according to the determined order. The source ranks are copied to the selected target ranks using the source and target device adaptors indicated in the device adaptor assignment data structure.

Abstract: Provided are a computer program product, system, and method for assigning device adaptors to use to copy source extents in source ranks to target extents in target ranks in a copy relation. A determination is made of an order of the target ranks in the copy relation. Target ranks in the copy relation are selected according to the determined order. For each selected target rank, indication is made in a device adaptor assignment data structure of a source device adaptor and target device adaptor of the device adaptors to use to copy the source rank to the selected target rank indicated in the copy relation, wherein indication is made for the selected target ranks according to the determined order. The source ranks are copied to the selected target ranks using the source and target device adaptors indicated in the device adaptor assignment data structure.

Abstract: For dynamically adjusting write pacing, a calculation module calculates an interval as a maximum threshold for a primary volume divided by a first maximum pacing level for a first importance level. The calculation module further calculates a first pacing level as a number of record sets that have not been mirrored to a secondary volume divided by the interval. The first pacing level is set to the first maximum pacing level if the first pacing level is greater than the first maximum pacing level. The calculation module also selects a first pacing delay associated with the first pacing level from a delay table. A pacing module delays writes for a first channel command word writing to the primary volume by the first pacing delay.

Abstract: In one embodiment of the present description, a copy relationship is established between a storage location at a first site and a storage location at a second site in a data storage system, wherein a dynamically assignable bitmap preset to one of a plurality of different predetermined bit patterns is selected as a function of both the availability of the selected bitmap and the type of predetermined bit pattern identified for the selected bitmap. The selected bitmap may be assigned as an out-of-sync bitmap wherein updates to the storage location at one site, which are to be copied to the storage location at the other site, are indicated in the selected bitmap, and data writes being written to the storage location at the one site, are copied to the storage location at the other site, using the selected bitmap as an out-of-sync bitmap. Other aspects are described.

Abstract: In one embodiment of the present description, mirroring is provided for a pair of storage units in bidirectional synchronous mirror relationships, and a tertiary storage unit. The mirroring includes multi-target mirroring to write updates written to the first storage unit to both the second storage unit and to a third storage unit. Similarly, for updates written to the second storage unit, multi-target mirroring is employed to write those to both the first storage unit and to the third storage unit. Other aspects are described.

Abstract: Provided are a computer program product, system, and method for managing updates and copying data in a point-in-time copy relationship expressed as source logical addresses and target logical addresses. A copy relationship indicates a source set of a subset of source logical addresses to copy to a target set comprising a subset of target logical addresses. An update is received to a source logical address that has not been copied. Determinations are made of the target logical address corresponding to the source logical address to be updated according to the copy relationship, a target group of target logical addresses in the target set that include the determined target logical address, and the source logical addresses in the source set that correspond to the target logical addresses in the target group. The determined source logical addresses are copied to the target logical addresses in the determined target group.

Abstract: Provided are a computer program product, system, and method for processing a copy command indicating a source set comprising a subset of source logical addresses to copy to an indicated target set comprising a subset of target logical addresses. Complete is expected to be returned to the copy command in response to completing the copying of the source set to the target set. A point-in-time (PiT) copy establish command is generated in response to receiving the copy command, indicating the source and target sets in the copy command, The generated PiT copy command is executed to generate copy information indicating the source and target sets of source logical addresses and whether they have been copied to the target set. Complete is returned to the copy command after generating the copy information and before copying all the source logical addresses to the target logical addresses.

Abstract: In one embodiment of the present description, a copy relationship is established between a storage location at a first site and a storage location at a second site in a data storage system, wherein a dynamically assignable bitmap preset to one of a plurality of different predetermined bit patterns is selected as a function of both the availability of the selected bitmap and the type of predetermined bit pattern identified for the selected bitmap. The selected bitmap may be assigned as an out-of-sync bitmap wherein updates to the storage location at one site, which are to be copied to the storage location at the other site, are indicated in the selected bitmap, and data writes being written to the storage location at the one site, are copied to the storage location at the other site, using the selected bitmap as an out-of-sync bitmap. Other aspects are described.

Abstract: Provided are a computer program product, system, and method for managing updates and copying data in a point-in-time copy relationship expressed as source logical addresses and target logical addresses. A copy relationship indicates a source set of a subset of source logical addresses to copy to a target set comprising a subset of target logical addresses. An update is received to a source logical address that has not been copied. Determinations are made of the target logical address corresponding to the source logical address to be updated according to the copy relationship, a target group of target logical addresses in the target set that include the determined target logical address, and the source logical addresses in the source set that correspond to the target logical addresses in the target group. The determined source logical addresses are copied to the target logical addresses in the determined target group.

Abstract: A method for performing a write to a volume x in a cascaded architecture is described. In one embodiment, such a method includes determining whether the volume x has a child volume, wherein each of the volume x and the child volume have a target bit map (TBM) associated therewith. The method then determines whether the 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. Finding the HS volume includes comparing ages of mapping relationships upstream from the volume x in order to determine a source of the data. Once the HS volume is found, the method copies the data from the HS volume to the child volume and performs the write to the volume x. A method for performing a read is also disclosed herein.