Abstract: A computer-implemented method, according to one approach, is for converting an existing storage pool into an intended storage pool in place. The computer-implemented method includes: reordering volume extents in the existing storage pool such that physical rank extents of the volumes align with boundaries between rank extents of the intended storage pool. The ranks in the existing storage pool are also converted from first rank extent sizes to second rank extent sizes. Moreover, in response to converting the ranks in the existing storage pool, for each of the volumes: a temporary pause/lock is performed on a volume segment table (VST) entry which corresponds to the given volume, and the VST entry is populated with a new structure which corresponds to the respective second rank extent size.

Abstract: A computer-implemented method, according to one approach, is for converting an existing storage pool into an intended storage pool in place. The computer-implemented method includes: identifying a request to convert the existing storage pool having a first extent size into the intended storage pool having a second extent size, where the first extent size is larger than the second extent size. For each volume in the existing storage pool: a temporary pause/lock is performed on a volume segment table (VST) entry which corresponds to the given volume, and a new structure is applied to the VST entry. The new structure divides existing physical extents associated with the VST entry into two or more smaller physical extents. Furthermore, for each of the ranks in the existing storage pool, the given rank is converted from the first extent size to the second extent size.

Abstract: A computer-implemented method, according to one approach, is for converting an existing storage pool into an intended storage pool in place. The computer-implemented method includes: identifying a request to convert the existing storage pool having a first extent size into the intended storage pool having a second extent size, where the first extent size is larger than the second extent size. For each volume in the existing storage pool: a temporary pause/lock is performed on a volume segment table (VST) entry which corresponds to the given volume, and a new structure is applied to the VST entry. The new structure divides existing physical extents associated with the VST entry into two or more smaller physical extents. Furthermore, for each of the ranks in the existing storage pool, the given rank is converted from the first extent size to the second extent size.

Abstract: A computer-implemented method, according to one approach, is for converting an existing storage pool into an intended storage pool in place. The computer-implemented method includes: reordering volume extents in the existing storage pool such that physical rank extents of the volumes align with boundaries between rank extents of the intended storage pool. The ranks in the existing storage pool are also converted from first rank extent sizes to second rank extent sizes. Moreover, in response to converting the ranks in the existing storage pool, for each of the volumes: a temporary pause/lock is performed on a volume segment table (VST) entry which corresponds to the given volume, and the VST entry is populated with a new structure which corresponds to the respective second rank extent size.

Abstract: A computer-implemented method, according to one approach, includes: identifying a request to convert an existing storage pool having a smaller first rank extent size into an intended storage pool having a larger second rank extent size. Volume extents in the existing storage pool are reordered such that physical rank extents of the volumes align with boundaries between the rank extents of the intended storage pool. Each of the ranks in the existing storage pool are converted from the first to the second rank extent size. Thereafter, for each of the volumes: a temporary pause/lock is performed on a VST entry which corresponds to the given volume, and an existing structure associated with the VST entry which corresponds to the first rank extent size is removed. Furthermore, the VST entry is populated with a new structure which corresponds to the second rank extent size.

Abstract: Provided are a method, system, and article of manufacture for verifying a record as part of an operation to modify the record, A search request is received to determine whether a record matches a value. A first component executes the search request to determine if the record matches the value. The first component sends a verify request to a second component that did not execute the search request to execute the search request to determine whether the record matches the value. A result of the first and second components executing the search request is logged.

Abstract: Various embodiments provide systems and methods for migrating data. One system includes a small computer system interface logical unit number (SCSI LUN) configured to store protected data, a processor, and memory configured to store a peer-to-peer remote copy (PPRC) application. The processor is configured to execute the PPRC application to modify the protection in transmitted data and received data. One method includes receiving unprotected data, utilizing a PPRC application to add protection to the data to generate protected data, and storing the protected data in a protected SCSI LUN. Another method includes receiving, at a protected SCSI LUN, a request to transmit protected data, utilizing a PPRC application to strip the protection from the protected data to generate unprotected data, and transmitting the unprotected data to an unprotected SCSI LUN.

Abstract: A method for dynamically enabling and disabling use of XFR_RDY is disclosed herein. In one embodiment of the invention, such a method includes receiving a write command at a target and determining whether XFR_RDY is enabled or disabled for the write command. In the event XFR_RDY is disabled, the method determines whether one or more buffers are available at the target. If at least one buffer is available, the method processes the write command by writing data associated with the write command to the one or more buffers. The method then returns information indicating the number of buffers that are still available at the target after completing the write command. A corresponding apparatus and computer program product are also disclosed and claimed herein.

Abstract: Provided are a method, system, and article of manufacture for authenticating a processing system accessing a resource. An association of processing system identifiers with resources, including a first and second resources, is maintained. A request from a requesting processing system in a host is received for use of a first resource that provides access to a second resource, wherein the request is generated by processing system software and wherein the request further includes a submitted processing system identifier included in the request by host hardware in the host. A determination is made as to whether the submitted processing system identifier is one of the processing system identifiers associated with the first and second resources. The requesting processing system is provided access to the first resource that the processing system uses to access the second resource.

Abstract: Various embodiments provide systems and methods for migrating data. One system includes a small computer system interface logical unit number (SCSI LUN) configured to store protected data, a processor, and memory configured to store a peer-to-peer remote copy (PPRC) application. The processor is configured to execute the PPRC application to modify the protection in transmitted data and received data. One method includes receiving unprotected data, utilizing a PPRC application to add protection to the data to generate protected data, and storing the protected data in a protected SCSI LUN. Another method includes receiving, at a protected SCSI LUN, a request to transmit protected data, utilizing a PPRC application to strip the protection from the protected data to generate unprotected data, and transmitting the unprotected data to an unprotected SCSI LUN.

Abstract: Provided are a system and article of manufacture for providing an address format compatible with different addressing formats used for addressing different sized address spaces. An address format is used in an operating system to address storage space in a storage device comprising a first region and a second region of storage space. A first group of applications uses the address format to only address the storage space in the first region and is not coded to use the address format to access the second region and a second group of applications uses the address format to address the storage space in the first and second regions.

Abstract: A method for replicating I/O performance in data replication environments, such as PPRC environments, is described. In selected embodiments, such a method includes monitoring I/O workload at a primary storage device over a period of time, such as a period of hours, days, or months. The method then generates learning data at the primary storage device describing the I/O workload over the selected time period. The learning data is replicated from the primary storage device to a secondary storage device. The method uses the learning data to optimize the secondary storage device to handle the I/O workload of the primary storage device. This will enable the secondary storage device to provide substantially the same I/O performance as the primary storage device in the event a failover occurs. A corresponding system and computer program product are also disclosed and claimed herein.

Abstract: A method for replicating I/O performance in data replication environments, such as PPRC environments, is described. In selected embodiments, such a method includes monitoring I/O workload at a primary storage device over a period of time, such as a period of hours, days, or months. The method then generates learning data at the primary storage device describing the I/O workload over the selected time period. The learning data is replicated from the primary storage device to a secondary storage device. The method uses the learning data to optimize the secondary storage device to handle the I/O workload of the primary storage device. This will enable the secondary storage device to provide substantially the same I/O performance as the primary storage device in the event a failover occurs.

Abstract: A method to maintain write operation atomicity where a write operation crosses a data storage medium track boundary. The method supplies a storage controller comprising a host adapter, a processor, and a NVS. The host adapter receives from a host computer a write request and data. The method determines if the write request will cross a data storage medium track boundary. If the write request will cross a data storage medium track boundary, the method indicates to the host adapter that the write request comprises a two-track transfer, and writes the data to the NVS as the data is received. If the host computer fails prior to providing all the data to the storage controller, the method discards the data written to the NVS to ensure write operation atomicity.

Abstract: A method to adjust a multi-path device reservation by supplying a computing device and a storage controller interconnected with a communication link. The method further reserves a data storage device in communication with the storage controller, where that data storage device reservation is held by a first communication path group comprising a first plurality of communication paths configured in the communication link. If the method detects a failed communication path configured in the first communication path group, the method configures a second communication path group by removing the failed communication path from the first communication path group, wherein the second communication path group maintains the data storage device reservation.

Abstract: Provided are a method, system, and article of manufacture for authenticating a processing system accessing a resource. An association of processing system identifiers with resources, including a first and second resources, is maintained. A request from a requesting processing system in a host is received for use of a first resource that provides access to a second resource, wherein the request is generated by processing system software and wherein the request further includes a submitted processing system identifier included in the request by host hardware in the host. A determination is made as to whether the submitted processing system identifier is one of the processing system identifiers associated with the first and second resources. The requesting processing system is provided access to the first resource that the processing system uses to access the second resource.

Abstract: Provided are a method, system, and article of manufacture for determining whether to use a repository to store data updated during a resynchronization. Writes to a primary storage are transferred to a secondary storage. A logical copy of the secondary storage as of a point-in-time is established. Writes to the secondary storage in the logical copy received from the primary storage during a logical copy duration after the point-in-time are stored in a repository that comprises less storage space than the secondary storage in the logical copy. The transferring of writes to the secondary storage is suspended. During the suspension writes to the primary storage are indicated in an out-of-synch data structure.

Abstract: Provided are a method, system, and article of manufacture for authenticating a processing system accessing a resource. An association of processing system identifiers with resources, including a first and second resources, is maintained. A request from a requesting processing system in a host is received for use of a first resource that provides access to a second resource, wherein the request is generated by processing system software and wherein the request further includes a submitted processing system identifier included in the request by host hardware in the host. A determination is made as to whether the submitted processing system identifier is one of the processing system identifiers associated with the first and second resources. The requesting processing system is provided access to the first resource that the processing system uses to access the second resource.

Abstract: A first unit and a second unit are provided in a multi-layer computing system, wherein the first unit is at a higher layer than the second unit in the multi-layer computing system, and wherein the first unit is a higher level unit and the second unit is a lower level unit. The higher level unit sends to the lower level unit, information to adjust a threshold for failure of components coupled to the lower level unit, wherein the higher level unit has more information on a degree of redundancy in the multi-layer computing system than the lower level unit. The lower level unit adjusts the threshold for the failure of the components, by using the information sent from the higher level unit.

Abstract: Provided are a method, system, and program for an adaptor to read and write to system memory. A plurality of blocks of data to write to storage are received at an adaptor. The blocks of data are added to a buffer in the adaptor. A determination is made of pages in a memory device and I/O requests are generated to write the blocks in the buffer to the determined pages, wherein two I/O requests are generated to write to one block split between two pages in the memory device. The adaptor executes the generated I/O requests to write the blocks in the buffer to the determined pages in the memory device.