Abstract: An enhanced mechanism for providing data protection for variable length records utilizes high performance block storage metadata. In an embodiment, an emulated record that emulates a variable length record, such as a Count-Key-Data (CKD) record or an Extended-Count-Key-Data (ECKD) record, is generated by a Host Bus Adapter (HBA) of a mainframe system. The emulated record comprises a sequence of extended fixed-length blocks, each of which includes a data block and a footer. A confluence of the footers defines a high performance block storage metadata unit associated with the emulated record and includes a checksum that covers all data blocks and all footers of the entire emulated record. In one embodiment, the checksum is checked during transit of the emulated record between a HBA and a storage subsystem (e.g.

Abstract: A file system driver stored in a computational device receives a request to provide access to a snapshot of a rewritable file system at a selected point in time, wherein a plurality of tokens corresponding to a plurality of data units are stored in the rewritable file system, and wherein an ordering relationship is maintained among the plurality of tokens. The file system driver determines a token corresponding to the selected point in time based on the ordering relationship. A virtual subdirectory name is generated corresponding to the determined token. A virtual subdirectory is created with the generated virtual subdirectory name, wherein the virtual subdirectory is a subdirectory of a root directory. The snapshot is accessed via the subdirectory.

Abstract: An apparatus, system, and method are disclosed for determining prefetch data. A start module communicates a start of a target software process to a storage device. A learning module learns data blocks accessed for the target software process. In one embodiment, a prefetch module prefetches the learned data blocks in response to the start of the target software process. An end module communicates the end of the target software process to the storage device. In one embodiment, the prefetch module terminates prefetching data blocks and the learning module terminates learning the data blocks accessed for the target software process in response to the end module's communication of the end of the target software process.

Abstract: A file system driver stored in a computational device receives a request to provide access to a snapshot of a rewritable file system at a selected point in time, wherein a plurality of tokens corresponding to a plurality of data units are stored in the rewritable file system, and wherein an ordering relationship is maintained among the plurality of tokens. The file system driver determines a token corresponding to the selected point in time based on the ordering relationship. A virtual subdirectory name is generated corresponding to the determined token. A virtual subdirectory is created with the generated virtual subdirectory name, wherein the virtual subdirectory is a subdirectory of a root directory. The snapshot is accessed via the subdirectory.

Abstract: A file system driver stored in a computational device receives a request to provide access to a snapshot of a rewritable file system at a selected point in time, wherein a plurality of tokens corresponding to a plurality of data units are stored in the rewritable file system, and wherein an ordering relationship is maintained among the plurality of tokens. The file system driver determines a token corresponding to the selected point in time based on the ordering relationship. A virtual subdirectory name is generated corresponding to the determined token. A virtual subdirectory is created with the generated virtual subdirectory name, wherein the virtual subdirectory is a subdirectory of a root directory. The snapshot is accessed via the subdirectory.

Abstract: Provided are a method, system, and article of manufacture for splitting writes between a storage controller and replication engine. A splitter executing in a storage controller manages access to primary volumes. An initialization command is received to communicate with a replication engine. A replication command is received for one primary volume and the primary volume is indicated as subject to replication. A write request is received to write data to a target primary volume of the primary volumes that is indicated as subject to the replication. The data in the write request is written to the target primary volume. The data in the write request is sent to the replication engine. The replication engine executes a copy services function associated with the target primary volume to write the data to a replication engine volume.

Abstract: An enhanced mechanism for providing data protection for variable length records utilizes high performance block storage metadata. In an embodiment, an emulated record that emulates a variable length record, such as a Count-Key-Data (CKD) record or an Extended-Count-Key-Data (ECKD) record, is generated by a Host Bus Adapter (HBA) of a mainframe system. The emulated record comprises a sequence of extended fixed-length blocks, each of which includes a data block and a footer. A confluence of the footers defines a high performance block storage metadata unit associated with the emulated record and includes a checksum that covers all data blocks and all footers of the entire emulated record. In one embodiment, the checksum is checked during transit of the emulated record between a HBA and a storage subsystem (e.g.

Abstract: Provided are a method, system, and article of manufacture for splitting writes between a storage controller and replication engine. A splitter executing in a storage controller manages access to primary volumes. An initialization command is received to communicate with a replication engine. A replication command is received for one primary volume and the primary volume is indicated as subject to replication. A write request is received to write data to a target primary volume of the primary volumes that is indicated as subject to the replication. The data in the write request is written to the target primary volume. The data in the write request is sent to the replication engine. The replication engine executes a copy services function associated with the target primary volume to write the data to a replication engine volume.

Abstract: 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.

Abstract: Provided are a method, system, and article of manufacture for splitting writes between a storage controller and replication engine. A splitter executing in a storage controller manages access to primary volumes. An initialization command is received to communicate with a replication engine. A replication command is received for one primary volume and the primary volume is indicated as subject to replication. A write request is received to write data to a target primary volume of the primary volumes that is indicated as subject to the replication. The data in the write request is written to the target primary volume. The data in the write request is sent to the replication engine. The replication engine executes a copy services function associated with the target primary volume to write the data to a replication engine volume.

Abstract: Provided are a method, system, and article of manufacture for controlling a first storage system receiving commands from a first and second managers to create a consistency group with a second storage system. Host writes are received at the first storage system, wherein the first storage system includes a first storage system primary site and a first storage system secondary site. The first storage system sends the host writes from the first storage system primary site to the first storage system secondary site. Host write operations are quiesced at the first storage system in response to a first command from a first manager. Host write operations are resumed at the first storage system in response to receiving a second command from the first manager. The first storage system receives a run command with a marker, wherein the marker indicates a cycle number to control the cycles of the first and second storage systems.

Abstract: A plurality of data units with associated timestamps is stored in a time based file system, wherein a timestamp corresponds to a time indicated by a system clock. A time indicated by the system clock is changed while the plurality of data units is being stored. A plurality of epochs is stored in a data structure, wherein an epoch is a period of time between a starting and an ending timestamp selected from the timestamps, and wherein successive epochs have overlapping time periods. The time based file system is reverted to an earlier point in time based on the plurality of epochs stored in the data structure.

Abstract: Provided are a method, system, and article of manufacture for managing consistency groups using heterogeneous replication engines replicating data. A common linkage manager issues a prepare to create consistency group command to a first replication manager and a second replication manager, wherein the first and second replication managers issue create consistency group commands to first and second replication engines, respectively, to form a consistency group of data at a first source storage and a second source storage to copy to a first target storage and second target storage, respectively.

Abstract: Generating a consistent point in time copy of data in a source volume and a target volume is achieved responsively to a first data modification request by writing a first altered version of the data onto a single source volume, asynchronously transferring the first altered version from the first storage site to a target volume located at a remote second storage site, while avoiding copying the first altered version onto other volumes at the first storage site. While asynchronously transferring the first altered version de-queuing a second modification request, and responsively to the second modification request synchronously transferring the first altered version from the first storage site to the target volume. Then a second altered version of the data is written to the single source volume and a copy transferred to the target volume in like manner.

Abstract: An enhanced mechanism for the allocation, organization and utilization of high performance block storage metadata provides a stream of data (e.g., in a server system, storage system, DASD, etc.) that includes a sequence of fixed-size blocks which together define a page. Each of the fixed-size blocks includes a data block and a footer. A high performance block storage metadata unit associated with the page is created from a confluence of the footers. Each footer in the confluence of footers has space available for application metadata, which are provided as one or more information units. At least one of the footers includes a Checksum field containing a checksum that covers at least the confluence of footers. This approach is advantageous in that it provides data integrity protection, protects against stale data, and significantly increases the amount of metadata space available for application use.

Abstract: Providing extended or end-to-end data integrity through layers of a system. In one aspect, information is to be transmitted between an application end of the system and a physical storage medium that stores the information for a database of the system, the information to be transmitted via a database server in a database server layer of the system. At least a portion of data protection is provided for the information, the data protection causing the information to be protected from corruption between a system layer and the physical storage medium, where the system layer is a separate layer provided closer to the application end of the system than the database server layer.

Abstract: Provided are a method, system, and article of manufacture for a replication engine communicating with a splitter to split writes between a storage controller and replication engine. Communication is initiated with the splitter implemented in a storage controller managing access to primary volumes. A command is sent to the splitter to copy writes to one primary volume to the replication engine. Write data is received from the splitter to one of the primary volumes following the splitter receiving the command to copy the writes to the replication engine. A determination is made of a copy services function to use for the received data. The determined copy services function is invoked to transfer the received data to a secondary storage volume.

Abstract: Data and metadata are generated in a computational device, wherein the generated data is stored in a first physical storage device coupled to the computational device, and wherein the generated metadata is stored transiently in the computational device. The data and the metadata are replicated to a second physical storage device. The replicated data and the replicated metadata in the second physical storage device are used to recover from a failure of at least one of the computational device and the first physical storage device.

Abstract: Tokens corresponding to data units written to a rewritable file system are stored, where an ordering relationship is maintained among the tokens, where the ordering relationship is such that a first token corresponding to a first data unit is of a lesser numerical value in comparison to a second token corresponding to a second data unit, and where the first data unit is written at an earlier point in time in comparison to the second data unit. The rewritable file system is reverted to an indicated point in time based on the ordering relationship that is maintained among the stored tokens.

Abstract: Provided are a method, system, and article of manufacture for copying writes from primary storages to secondary storages across different networks. A failure notification is communicated, using a first network protocol, from a primary device in a first group of at least one primary device and at least one corresponding primary storage managed by the at least one primary device to a control system in response to the primary device determining that a write to the primary storage cannot be copied to a corresponding secondary storage. A failure notification is communicated, using a second network protocol, from a primary device in a second group of at least one primary device and at least one corresponding primary storage managed by the at least one primary device to the control system in response to the primary device determining that a write to the corresponding primary storage cannot be copied to a corresponding secondary storage.