Source: https://patents.google.com/patent/US10176048B2/en
Timestamp: 2019-04-19 04:38:51+00:00

Document:
2014-09-16 Assigned to INTERNATIONAL BUSINESS MACHINES CORPORATION reassignment INTERNATIONAL BUSINESS MACHINES CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: JAQUETTE, GLEN A., KISHI, GREGORY T.
Provided are a computer program product, system, and method for creating a restore copy from a copy of source data in a repository having source data at different point-in-times and reading data from the repository for the restore copy. The source data is copied as of an initial point-in-time to a repository. Point-in-time copies at different point-in-times of the source data are initiated following the initial point-in-time. Change information for the point-in-time copy indicating changed data in the source data that changed between the point-in-time of the point-in-time copy and a subsequent point-in-time are transmitted to the repository. For each point-in-time copy, changed source data indicated in the change information for the point-in-time copy as changed is copied to the repository. A restore copy is returned to a restore request before the source data in the repository as of a restore point-in-time is copied to the restore copy.
The present invention relates to a computer program product, system, and method for creating a restore copy from a copy of source data in a repository having source data at different point-in-times and reading data from the repository for the restore copy.
In a storage environment, a storage controller may create point-in-time (“PiT”) copies of a production volume using point-in-time copy techniques, such as the IBM FlashCopy® (FlashCopy is a registered trademark of IBM), snapshot, etc. A point-in-time copy replicates data in a manner that appears instantaneous and allows a host to continue accessing the source volume while actual data transfers to the copy volume are deferred to a later time. The PiT copy appears instantaneous because complete is returned to the copy operation in response to generating the relationship data structures without copying the data from the source to the target volumes. PiT copy techniques typically defer the transfer of the data in the source volume at the time the PiT copy relationship was established to the copy target volume until a write operation is requested to that data block on the source volume. Data transfers may also proceed as a background copy process with minimal impact on system performance. The PiT copy relationships that are immediately established in response to the PiT copy command include a bitmap or other data structure indicating the location of blocks in the volume at either the source volume or the copy volume. The PiT copy comprises the combination of the data in the source volume and the data to be overwritten by the updates transferred to the target volume.
When an update to a block in the source volume involved in a PiT copy relationship is received, the copy of the track as of the point-in-time must be copied to side file or the target volume before the new data for the track is written to the source volume, overwriting the point-in-time copy of the data.
Provided are a computer program product, system, and method for creating a restore copy from a copy of source data in a repository having source data at different point-in-times and reading data from the repository for the restore copy. The source data is copied as of an initial point-in-time to a repository. Point-in-time copies at different point-in-times of the source data are initiated following the initial point-in-time. In response to completing each of the point-in-time copies, transmitting to the repository change information for the point-in-time copy indicating changed data in the source data that changed between the point-in-time of the point-in-time copy and a subsequent point-in-time. For each point-in-time copy, copying changed source data comprising source data indicated in the change information for the point-in-time copy as changed to the repository. Receiving a restore request to restore the source data as of a restore point-in-time. The restore copy is returned to the restore request before the source data in the repository as of the restore point-in-time is copied to the restore copy.
FIG. 1 illustrates an embodiment of a storage environment.
FIG. 2 illustrates an embodiment of storage controller point-in-time copy information.
FIG. 3 illustrates an embodiment of repository point-in-time copy information.
FIG. 4 illustrates an embodiment of operations to create a repository having source data at different point-in-times.
FIGS. 5a, 5b, and 5c illustrate examples of states of the source data and the repository at different point-in-times.
FIG. 6 illustrates an embodiment of operations to create a restore copy.
FIG. 7 illustrates an embodiment of restore copy information.
FIG. 8 illustrates an embodiment of data unit information in the restore copy information for each data unit in the restore copy.
FIG. 9 illustrates an embodiment of operations to generate restore copy information.
FIG. 10 illustrates an embodiment of operations to process a write request to a restore copy.
FIG. 11 illustrates an embodiment of operations to process a read request to the restore copy.
FIG. 12 illustrates an embodiment of a storage environment including virtual machines.
FIG. 13 illustrates a computing environment in which the components of FIGS. 1 and 12 may be implemented.
Described embodiments provide techniques for creating a repository to maintain a full copy of the source data and point-in-time copies of the source data to allow the source data to be restored from the repository at different point-in-times. Further, with described embodiments, the operations to maintain the point-in-time (“PiT”) copy information in the repository and perform the restore operations may be performed by a program component separate from the storage controller logic creating the PiT copies from the source data, so that the repository is separately maintained, used, and managed from the storage controller. Yet further, with described embodiments, a restore copy may be created and data requests to the data units in the restore copy may be returned from the repository to return data units as of a restore point-in-time of the restore copy.
FIG. 1 illustrates an embodiment of a data storage environment having a storage controller 100 managing access to a first storage 102 that includes source data 104, such as a production volume used by different host systems. A host 106 includes a repository copy manager program 108 to manage the copying of the source data 104 to a repository 110 in a second storage 112. The storage controller 100, host 106, and second storage 112 may communicate over a network 114.
The storage controller 100 includes a point-in-time (“PiT”) copy manager 116 to create point-in-time copies of the source data 104, e.g., FlashCopy, snapshot, etc. When creating a PiT copy, the PiT copy manager 116 generates PiT copy information 200 on the PiT copy created as of a point-in-time. The storage controller 100 further includes an operating system 118, including the code and logic to manage Input/Output (“I/O”) requests to the source data 104. The operating system 118 may configure the source data 104 in one or more volumes and data is stored in data units, such as tracks, logical block addresses (LBAs), extents, etc. The PiT copy manager 116 may be a copy service supplied with the operating system 118.
The storages 102 and 112 may store tracks in a Redundant Array of Independent Disks (RAID) configuration where strides of tracks are written across multiple storage devices comprising the storages 102 and 112. The storages 102 and 112 may each comprise one or more storage devices known in the art, such as interconnected storage devices, where the storage devices may comprise hard disk drives, solid state storage device (SSD) comprised of solid state electronics, such as a EEPROM (Electrically Erasable Programmable Read-Only Memory), flash memory, flash disk, Random Access Memory (RAM) drive, storage-class memory (SCM), etc., magnetic storage disk, optical disk, tape, etc.
The network 114 may comprise a network such as one or more interconnected Local Area Networks (LAN), Storage Area Networks (SAN), Wide Area Network (WAN), peer-to-peer network, wireless network, etc.
The PiT copy manager 116 performs a PiT copy operation that replicates data in a manner that appears instantaneous and allows a process to continue accessing the source volume while actual data transfers to the copy volume are deferred to a later time. The PiT copy appears instantaneous because complete is returned to the copy operation in response to generating the relationship data structures without copying the data.
The repository copy manager 108 copies changed data of the source data 104 at different point-in-times to changed data 120 in the repository 110, including an initial copy of all the source data, and copies the PiT copy information 200 at the storage controller 100 to the repository 110 to store as repository PiT copy information 300 in the repository 110. The repository copy manager 108 uses the PiT copy information 300 to determine changed data at the source data 104 to copy to the changed data 120. To copy all the source data as of an initial point-in-time to the repository 110, the repository copy manager 108 may modify the change information for the initial PiT copy, or PiT bitmap, having a bit for each data unit in the source data 104 to indicate that all the source data has changed to generate modified initial change information 200 0′ that indicates that each data unit in the source data 104 has changed. The repository copy manager 108 may then copy all the source data 104 units in the modified initial change information 200 0′ to the changed data 120 in the repository 110 to provide a full copy of the source data 104 as of the initial point-in-time (T0) in the repository. The repository copy manager 108 would use the change information in PiT copy information 200 for PiT copies following the initial point-in-time to copy changed data at different point-in-times to the changed data 120 in the repository 110.
With described embodiments, the repository copy manager 108 maintains a separate full copy of the source data 104 and the PiT copy information 300 of the source data 104 in a separate storage 112 so that data can be restored to different point-in-times independently of the source data 104 in the first storage 102 and the PiT copy information 200 a at the storage controller 100. Thus, the repository 110 by allowing for independent restore of the source data 104 provides a secure backup independent to protect from failure at the storage controller 100 or first storage 102.
In certain embodiments, the creation and management of the repository 110 is managed by a repository copy manager 108 that is separate from the storage controller 100 programs, such as the PiT copy manager 116 that creates the PiT copies.
The host 106 may further include a restore copy I/O manager 126 to manage I/O requests directed to restore copies 124 to ensure that data as of a restore time for which the restore copy 124 is create is returned from the restore copy 124 or the repository 110.
To generate the restore copy 124, the repository copy manager 108 may utilize restore copy information 130 indicating the source data in the changed data 120 that needs to be copied to the restore copy 124.
In the embodiment of FIG. 1, the repository creation and restore operations may be performed by program components, such as the repository copy manager 108 and the restore copy I/O manager 126, that are separate from the storage controller logic, e.g., the PiT copy manager 116 that created the PiT copies. In an alternative embodiment, the repository copy manager 108, the repository copy I/O manager 126, and/or the repository 110 may be maintained on the storage controller 100.
FIG. 2 illustrates an instance of the PiT copy information 200, for PiT copy at time Ti, which may comprise information maintained for the storage controller PiT copy information 200, and may include a PiT copy identifier 202 identifying the PiT copy created by the PiT copy manager 116 at the storage controller 100; a point-in-time 204 of the PiT copy 202, which may mean that data is consistent as of that point-in-time 204; change information 206 indicating which data or tracks in the source data 104 has changed since the point-in-time 204 and while the PiT copy 202 was open, which may comprise a bitmap having a bit for each data unit (e.g., track) that is set to one of two values indicating the data or track represented by the bit has or has not been updated since the point-in-time 204; and indicate the changed PiT data 208 comprising the data at the point-in-time 204 that was changed after the point-in-time 204 while the PiT copy 202 was open and still being updated. PiT copy information may be maintained for an initial PiT copy taken at the initial time T0 and for subsequent PiT copies taken at subsequent point-in-times.
In one embodiment, the PiT copy may be completed or frozen at a time subsequent to the point-in-time 204, such that the changed PiT data 208 includes data changed from the point-in-time 204 until the PiT copy 202 was completed, e.g., frozen or a new PiT copy initiated, and does not include changed data after the PiT copy 202 was completed, e.g., frozen. A PiT copy 202 may be completed upon a freeze command or initiating a subsequent PiT copy at a subsequent point-in-time to the point-in-time 204. A completed PiT copy 202 may be consistent as of the point-in-time. Other techniques may be used to complete, e.g., freeze, the PiT copy.
FIG. 3 illustrates an embodiment of an instance of PiT copy information 300, maintained in the repository 110, that is generated from an instance of PiT copy information 200, from the storage controller 100, and includes a PiT copy identifier 302 identifying the PiT copy 202 created by the PiT copy manager 116 at the storage controller 100; a point-in-time 304 of the PiT copy 302, which may mean that data is consistent as of that point-in-time 304; change information 306 indicating which data or tracks in the source data 104 has changed since the point-in-time 304 and while the PiT copy 302 was open, which may comprise a bitmap; and a repository offset 308 indicating an offset in the changed data 120 at which the data indicated in the change information 306 for the PiT copy 302 is located. The location in the changed data 120 of a particular changed data unit for a PiT copy 302 can be determined at an offset from the repository offset 208 in the changed data 120, such as by summing the repository offset 208 with the number of the changed unit indicated in the change information 306, i.e., the jth data unit, times a length of the data unit. In this way, changed data from a PiT copy 300 are written sequentially after the last written data in the change data 120 in the repository 110.
FIG. 4 illustrates an embodiment of operations performed by the repository copy manager 108 and the PiT copy manager 116 to copy the source data 104 to the repository 110 at different points-in-time from the PiT copies for the source data 104, such as a production volume, created by the PiT copy manager 116. Upon initiating (at block 400) repository copy operations for source data 104, the repository copy manager 108 sends (at block 402) a command to the PiT copy manager 116 to create an initial PiT copy 200 0 at an initial point-in-time, referred to herein as T0. The repository copy manager 108 may modify the initial change information 200 0 to generate modified initial change 200 0′ indicating that all source data units in the source data have changed. The repository copy manager 108 may send (at block 406) to the repository 110 the modified initial change information 200 0′, which indicates that all data units have changed and the changed PiT data 208 0 for the initial PiT copy (T0) indicated in the modified initial change information 200 0′, which indicates all the source data as changed. All the source data as of the initial point-in-time is copied to the changed data 120 in the repository 110. The PiT copy 200 0′ from the storage controller 100 would be stored as PiT copy information 300 0 with a repository offset 308 of zero because the start of the data from the initial PiT copy T0 is stored at the beginning of the changed data 120 in the repository 110.
The repository copy manager 108 may send (at block 408) a command to the PiT copy manager 116 to create a subsequent PiT copy (Ti+1) at a subsequent point-in-time Ti+1, which would result in PiT copy information 200 (i+1). In one embodiment, the repository copy manager 108 may send individual commands to the PiT copy manager 116 to create PiT copies and freeze a previously created PiT copy. In an alternative embodiment, the repository copy manager 108 may send one command to the PiT copy manager 116 to instruct it to periodically create PiT copies of the source data 104, where the creation of a subsequent PiT copy freezes the previously created PiT copy. Still further, the PiT copy manager 116 at the storage controller 100 may be independently creating PiT copies without prompting from the repository copy manager 108.
Upon determining (at block 410) that the previous point-in-time copy at Ti completed, the repository copy manager 116 sends (at block 412) to the repository 110 for storage the PiT copy information 200 i for the PiT copy at time Ti, including the change information 206 i and the changed PiT data 208 i to store in the repository PiT copy information 300 i for Ti. In one embodiment, a PiT copy at point-in-time Ti may be completed upon the creation of the subsequent PiT copy at time Ti+1. In an alternative embodiment, a PiT copy may be completed by issuing a freeze command to freeze the PiT copy so that the change information 206 stops indicating changes to the source data 104. The repository copy manager 108 creates (at bock 414) in the repository PiT copy information 300, from the received PiT copy information 200 i.
The repository copy manager 108 may transmit (at block 416) the source data 104 at the subsequent time (Ti+1) that has changed since the previous time to the changed data 120 in the repository 110 to make the full copy current as of the subsequent time Ti+1. To perform this operation, the repository copy manager 108 may determine from the change information 206 for the previous PiT copy at Ti the data units in the source data 104 that have changed and then copy those data units from the source data 104 to the changed data 120. In this way, at the subsequent point-in-time Ti+1 when the subsequent PiT copy (Ti+1) is created, data units in the source data 104 that have changed between the previous point-in-time Ti and the subsequent point-in-time Ti+1 are copied to the changed data 120 in the repository 110.
The repository copy manager 108 may indicate (at block 418) in the repository offset 308 the data unit offset in the changed data 120 where the changed data for the PiT copy at Ti begins in the changed data 120. If (at block 420) further point-in-time copies are to be created, then the repository copy manager 108 considers (at block 422) the current subsequent point-in-time copy at (Ti+1) to be the previous point-in-time copy at Ti during the next iteration of processing the next PiT copy. In this way, i is effectively incremented as the current subsequent point-in-time Ti+1 becomes the previous point-in-time and a next point-in-time becomes the new subsequent point-in-time. Control then proceeds back to block 408 to create or process a new subsequent PiT copy (Ti+i) at a new subsequent point-in-time Ti+1. If (at block 420) there are no further PiT copies to process, then control ends.
With the described embodiments of FIG. 4, a repository 110 of a full copy of the source data 104 having PiT copy information for different PiT copies is created independently of the storage controller 100 operations to create the PiT copies. In this way, the logic or operations of the repository management operations are independent of the storage controller 100 logic to create PiT copies.
FIGS. 5a, 5b, 5c illustrate examples of the operations of FIG. 4 to copy all the source data at different point-in-times to the changed data 120 and repository PiT copy information 200 b. FIG. 5a shows the state at an initial time T0 of the source data 104 0 in the source storage 102 that is copied to the changed data 120 0 in the repository 110, which may comprise all the source data 104 as of the initial time T0. Further, a PiT information copy 200 0 is created at the initial time T0 which has change information 206 0′ indicating that all the source data has changed at the storage controller 100.
FIG. 5b shows a time T1 when a second PiT copy 200 1 at T1 is created, which may result in the completion or freezing of the previous PiT copy 200 0 at T0 having changed data 208 0 as of the point-in-time T0 before changes occurring between T0 and T1. The repository copy manager 108 copies the changed data between T0 and T1, shown as units 520 and 522, to the changed data 120 1 in the repository 110 to update the changed data 120 1 to have changed data 520, 522 as of T1, which follows the initial written data. Further, the completed, or frozen, PiT copy information 200 0 at T0 is copied to the repository 110 to store as repository PiT copy 300 0, which includes an offset 308 0 indicating zero because the source data for the initial PiT copy 200 0 is the first data written to the changed data 120 1.
FIG. 5c shows a time T2 when a third PiT copy 200 2 at T2 is created, which may result in the completion or freezing of the PiT copy 200 1 at T1 having changed data 208 1 as of the point-in-time T1 before changes occurring between T1 and T2. The repository copy manager 108 copies the changed data between T1 and T2, shown as 524 and 526, to the repository 110 to update the changed data 120 2 to have data as of T2. Further, the completed, or frozen, PiT copy information 200 1 at T1 is copied to the repository 110 to store as repository PiT copy 300 1, which includes a repository offset 308 1 indicating the data unit offset in the repository 120 2 at which the changed data 520 and 522 begins.
FIG. 6 illustrates an embodiment of operations performed by the repository copy manager 108 to create a restore copy 124 from the repository 110 as of a restore time (TR), which may comprise a point-in-time of one of the repository point-in-time copies 200 b. Upon processing (at block 600) a restore request to create a restore copy of the source data as of the restore time (TR), the restore copy manager 108 configures (at block 602) an empty restore copy 124 or restore volume. The restore copy manager 108 may further generate (at block 604) restore copy information 130 for the restore copy having information on the changed data 120 that comprises the data for the restore3 copy 124 as of the restore point-in-time (TR). The empty restore copy 124 is returned (at block 606) to the restore request to make available for access immediately.
FIG. 7 illustrates an embodiment of restore copy information 700 generated at block 604 for a restore copy 124, including a restore copy identifier (ID) 702 identifying the restore copy; a restore point-in-time (TR) 704 the user selected to create the restore copy 124 to which the data from the changed data 120 for the restore is copied; a restore copy location 706 indicating a location in the second storage 112 at which the restore copy 702 is stored; and data unit information 708 providing information for each of the data units in the restore copy 702.
FIG. 8 illustrates an embodiment of an instance of data unit information 708, for data unit i indicating a data unit number 800 of the data unit i, which may comprise an integer number indicating a sequential number of the data unit in the source data 104, e.g., a block number; a copy bit 802 indicating whether the data unit 800 is located in the restore copy 124 or only in the repository 110; and a repository location 804 indicating a location, such as an offset, in the changed data 120 at which the data unit 800 is located in the repository 110. The repository location 804 may comprise an absolute byte location in the changed data 120 or comprise an offset, e.g., block number, from which the byte location can be determined by multiplying the offset times a data unit length. The repository location 804 is used to locate the data unit as of the restore time (TR) from multiple copies of the data unit in the changed data 120 at different point-in-times.
In alternative embodiments, the information used to locate the data units in the changed data 120 may be in different formats, such as indicating the PiT copy from which the data unit 800 is obtained or indicate other offset information that may be used to calculate the specific location in the changed data 120 of the data unit 800.
For each determined changed data unit at step 906, the repository copy manager 106 determines (at block 908) from the repository offset 308, for the PiT copy at Ti the location in the changed data 120 of the data unit. In one embodiment, the repository offset 308 may provide just information for the first changed data unit of the PiT copy and the repository copy manager 108 must determine the offset for a particular data unit based on the number of the changed data unit, i.e., jth changed data unit indicated in the PiT copy change information 306, plus the repository offset 308 i, then that sum times a data unit length. Alternatively, the repository offset 308 may indicate the offset number in the changed data 120 for each changed data unit for PiT copies following the initial PiT copy at T0.
For instance, in an embodiment, where the repository offset 308 i comprises an offset at which the changed data for the PiT copy at Ti begins in the changed data 120, the determined location may comprise the changed data unit number, comprising the number in the order in which the data unit was written for the PiT copy at Ti, plus the repository offset 308 i for the PiT copy at Ti, with this sum multiplied by the data unit length. For instance, if the data unit is the third data unit for the PiT copy at Ti written to the changed data 120 and the data unit number offset at which the changed data for the PiT copy at Ti begins in the change data 120 is 100, and the data unit length is 16 bytes, then the location for the data unit in the changed data 120 comprises the sum of three times 100 multiplied by 16, e.g., (3+100)×16, which equals 4800th byte in the changed data 120. For each determined changed data unit, the repository copy manager 108 indicates (at block 910) the determined location for the data unit in the repository location 804 for the data unit.
If (at block 914) Ti equals T0, then all repository PiT copies 300 at or before the restore time (TR) have been considered, and control ends. Otherwise, if Ti does not equal T0, then Ti is set (at block 916) to Ti−1 to proceed back to block 906 to consider the next PiT copy 300 i−1 immediately preceding the last considered PiT copy 300 i. With the operations of FIG. 9, changed data units are determined from the repository PiT copies 300 from the PiT copy closest to the restore time in reverse temporal order. In this way, if multiple PiT copies provide changed data for the same source data unit, then the changed data that is indicated for the restore copy being created comes from the PiT copy providing changed data for that data unit that is closest in time to the restore time TR so that the restore copy 124 is provided with changed data 120 from the repository 110 as of the restore time TR.
FIG. 10 illustrates an embodiment of operations performed by the restore copy I/O manager 126 to process a write request to the restore copy 124. Upon processing (at block 1000) a write request to the restore copy, the received write data is applied (at block 1002) to the restore copy 124.
FIG. 11 illustrates an embodiment of operations performed by the restore copy I/O manager 126 to process a read request to a requested data unit in the restore copy 124. Upon processing (at block 1100) the read request to a data unit j in the restore copy 124, if (at block 1102) the copy bit 802 j for data unit j indicates that the requested data unit is in the restore copy 124, then the data unit is accessed (at block 1104) from the restore copy 124 and returned to the request. Otherwise, if the request copy 124 does not store the requested data unit as of the restore time (TR), then the restore copy I/O manager 126 determines (at block 1106) from the repository 110 the location in the repository 110 for the changed data for a point-in-time copy having a point-in-time from the restore point-in-time to the initial point-in-time and closest in time to the restore point-in-time (e.g., indicated in the repository offset 308 j for the data unit j). The requested data unit j is accessed (at block 1108) from the determined location in the changed data 120 in the repository 110 to return to the read request. The accessed data unit j may be copied (at block 1110) to the restore copy 124 to make available for future read requests and the copy bit 802 j for data unit j is updated to indicate the data unit is in the restore copy 124. In an alternative embodiment, the accessed data unit may not be copied to the restore copy 124, and instead always returned from the changed data 120 in the repository 110.
With the described embodiments, the restore copy 124 may be generated almost instantaneously because no data needs be copied to the restore copy 124 before it is made available for access. Upon processing read request, the restore copy information 700 may be used to determine whether requested read data from the restore copy 124 is at the restore copy 124 or only in the changed data 120 to determine whether to return the requested data from the restore copy 124 or the changed data 120.
FIG. 12 illustrates an embodiment in which the host 1206 implements a plurality of virtual machines 1230 for which different restore copies 1224 are created for use by the different virtual machines 1230. Elements 1200, 1206, 1208, 1214, 1226, 1210, 1212, 1220, 1224 and 1230 in FIG. 12 are the same as corresponding elements 100, 106, 114, 108, 126, 110, 112, 120, 124, and 300 described with respect to FIG. 1. However, in FIG. 12, the repository copy manager 1208 creates restore copies 1224 for the different virtual machines 1230 to use and the restore copy I/O manager 1226 manages virtual machine 1230 read and write requests to their respective restore copies 1224 as discussed with respect to the restore copy I/O manager 126. In an alternative embodiment, each virtual machine 1230 may include its own instantiation of the repository copy manager 1208 and the restore copy I/O manager 1226. In this way, the different virtual machines 1230 may access their own separate restore copies 1224, and receive data as of the restore point-in-time (TR) from the repository PiT copy information 200 b if needed.
The computational components of FIG. 1 and FIG. 12, including the storage controller 100, 1200 and host 106, 1206 may be implemented in one or more computer systems, such as the computer system 1302 shown in FIG. 13. Computer system/server 1302 may be described in the general context of computer system executable instructions, such as program modules, being executed by a computer system. Generally, program modules may include routines, programs, objects, components, logic, data structures, and so on that perform particular tasks or implement particular abstract data types. Computer system/server 1302 may be practiced in distributed cloud computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed cloud computing environment, program modules may be located in both local and remote computer system storage media including memory storage devices.
As shown in FIG. 13, the computer system/server 1302 is shown in the form of a general-purpose computing device. The components of computer system/server 1302 may include, but are not limited to, one or more processors or processing units 1304, a system memory 1306, and a bus 1308 that couples various system components including system memory 1306 to processor 1304. Bus 1308 represents one or more of any of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, and a processor or local bus using any of a variety of bus architectures. By way of example, and not limitation, such architectures include Industry Standard Architecture (ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, Video Electronics Standards Association (VESA) local bus, and Peripheral Component Interconnects (PCI) bus.
Computer system/server 1302 typically includes a variety of computer system readable media. Such media may be any available media that is accessible by computer system/server 1302, and it includes both volatile and non-volatile media, removable and non-removable media.
System memory 1306 can include computer system readable media in the form of volatile memory, such as random access memory (RAM) 1310 and/or cache memory 1312. Computer system/server 1302 may further include other removable/non-removable, volatile/non-volatile computer system storage media. By way of example only, storage system 1313 can be provided for reading from and writing to a non-removable, non-volatile magnetic media (not shown and typically called a “hard drive”). Although not shown, a magnetic disk drive for reading from and writing to a removable, non-volatile magnetic disk (e.g., a “floppy disk”), and an optical disk drive for reading from or writing to a removable, non-volatile optical disk such as a CD-ROM, DVD-ROM or other optical media can be provided. In such instances, each can be connected to bus 1308 by one or more data media interfaces. As will be further depicted and described below, memory 1306 may include at least one program product having a set (e.g., at least one) of program modules that are configured to carry out the functions of embodiments of the invention.
Program/utility 1314, having a set (at least one) of program modules 1316, may be stored in memory 1306 by way of example, and not limitation, as well as an operating system, one or more application programs, other program modules, and program data. Each of the operating system, one or more application programs, other program modules, and program data or some combination thereof, may include an implementation of a networking environment. The components of the computer 1302 may be implemented as program modules 1316 which generally carry out the functions and/or methodologies of embodiments of the invention as described herein. The systems of FIGS. 1 and 12 may be implemented in one or more computer systems 1302, where if they are implemented in multiple computer systems 1302, then the computer systems may communicate over a network.
Computer system/server 1302 may also communicate with one or more external devices 1318 such as a keyboard, a pointing device, a display 1320, etc.; one or more devices that enable a user to interact with computer system/server 1302; and/or any devices (e.g., network card, modem, etc.) that enable computer system/server 1302 to communicate with one or more other computing devices. Such communication can occur via Input/Output (I/O) interfaces 1322. Still yet, computer system/server 1302 can communicate with one or more networks such as a local area network (LAN), a general wide area network (WAN), and/or a public network (e.g., the Internet) via network adapter 1324. As depicted, network adapter 1324 communicates with the other components of computer system/server 1302 via bus 1308. It should be understood that although not shown, other hardware and/or software components could be used in conjunction with computer system/server 1302. Examples, include, but are not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data archival storage systems, etc.
copying data from the source data in the repository, as of the initial point-in-time and the changed data for at least one point-in-time copy as of a point-in-time closest to the restore point- in-time, to the restore copy in response to read requests after the generated restore copy is returned and made available for immediate read and write access.
returning the requested data from the changed data for one of the point-in-time copies in the repository at a point-in-time from the restore point-in-time to the initial point-in-time in the repository in response to determining that the restore copy does not include the requested data.
returning the requested data from the restore copy in response to determining that the requested data is in the restore copy.
4. The computer program product of claim 2, wherein when multiple point-in-time copies in the repository provide changed data for the requested data, the changed data from the point-in-time copy having a point-in-time from the restore point-in-time to the initial point-in-time and closest in time to the restore point-in-time is returned as the requested data.
5. The computer program product of claim 1, wherein the point-in-time copies are generated by a point-in-time copy program and wherein a repository copy program executed separately from the point-in-time copy program performs the operations of copying to the repository the change information and the changed data at the subsequent point-in-time indicated in the change information as changed.
indicating for each point-in-time copy in the repository a repository offset for indicating an offset in the repository where the changed data for the point-in-time copy is written.
generating restore copy information indicating location information used to locate each data unit in the repository at which the source data for the data units in the repository are stored, wherein when multiple point-in-time copies provide changed data as of the restore point-in-time, the location information is determined from the repository offset for the point-in-time copy having a point-in-time from the restore point-in-time to the initial point-in-time and closest in time to the restore point-in-time, wherein returning the requested data from the repository comprises using the location information indicated in the restore copy information for the requested data to access the requested data from the repository.
indicating in the restore copy information the determined location in the repository for each of the determined changed data units.
applying the writes to update the restore copy.
returning the requested data from the changed data for one of the point-in-time copies in the repository to the requesting virtual machine.
copying data from the source data in the repository, as of the initial point-in-time and the changed data for at least one point-in-time copy as of a point-in-time closest to the restore point-in-time, to the restore copy in response to read requests after the generated restore copy is returned and made available for immediate read and write access.
13. The system of claim 12, wherein when multiple point-in-time copies in the repository provide changed data for the requested data, the changed data from the point-in-time copy having a point-in-time from the restore point-in-time to the initial point-in-time and closest in time to the restore point-in-time is returned as the requested data.
20. The method of claim 19, wherein when multiple point-in-time copies in the repository provide changed data for the requested data, the changed data from the point-in-time copy having a point-in-time from the restore point-in-time to the initial point-in-time and closest in time to the restore point-in-time is returned as the requested data.
"Notification_of_Reasons_for_Refusal" for JP Application No. 2016-548352, dated Sep. 18, 2018, pp. 6.
"Search Report by Registered Searching Organization", dated Sep. 18, 2018, JP Application No. 2016-548352, pp. 29.
Advisory Action dated Jan. 23, 2017, pp. 8, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Amendment dated May 10, 2017, pp. 15, to Final Office Action dated Feb. 10, 2017, pp. 29, for U.S. Appl. No. 14/175,980, filed Feb. 7, 2014.
Amendment dated Nov. 15, 2016, pp. 14, to Final Office Action dated Jul. 15, 2016, pp. 40, for U.S. Appl. No. 14/175,964, filed Feb. 7, 2014.
Burger, et al., IBM System Storage DS8000 Series: IBM FlashCopy SE, IBM Corporation, Document No. REDP-4368-00, pp. 80, Feb. 2008.
Chesarek, et al., "IBM System Storage FlashCopy Manager and PPRC Manager Overview", IBM Corporation, Document No. REDP-4065, pp. 62, 2008.
CN Office Action dated Jul. 3, 2018, pp. 7, for Application No. 201580007367.
Creating a Restore Copy From a Copy of a Full Copy of Source Data in a Repository That is at a Different Point-In-Time Than a Restore Point-In-Time of a Restore Request, by G.A. Jaquette et al., US Application Serial No. Unknown, filed Feb. 7, 2014.
Creating a Restore Copy From a Copy of Source Data in a Repository Having Source Data at Different Point-In-Times, by G.A. Jaquette et al., US Application Serial Unknown, filed Feb. 7, 2014.
Cronauer, et al., "IBM System Storage DS8000 Copy Services for Open Systems", IBM Corporation, Document No. SG24-6788-06, pp. 800, Feb. 2013.
English language translation of CN 102236589 filed Apr. 17, 2013.
English language translation of CN 103262043 filed Aug. 21, 2013.
English language translation of CN 1740981 filed Mar. 1, 2006.
English Machine Translation CN101149594, published Mar. 26, 2008.
English Machine translation of "Notification_of_Reasons_for_Refusal" for JP Application No. 2016-548352, dated Sep. 18, 2018, pp. 4.
English machine translation of "Search Report by Registered Searching Organization", JP Application No. 2016-548352, dated Sep. 18, 2018, pp. 34.
English Machine translation of CN Office Action dated Jul. 3, 2018, pp. 7, for Application No. 201580007367.
English Machine translation of CN1071770A, pp. 5, published.
Final Office Action dated Feb. 10, 2017, pp. 29, for U.S. Appl. No. 14/175,980, filed Feb. 7, 2014.
Final Office Action dated Feb. 20, 2018, pp. 32, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Final Office Action dated Feb. 23, 2018, pp. 37, for U.S. Appl. No. 14/175,975, filed Feb. 7, 2014.
Final Office Action dated Jul. 15, 2016, pp. 40, for U.S. Appl. No. 14/175,964, filed Feb. 7, 2014.
Final Office Action dated Sep. 22, 2016, pp. 33, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Final Office Action dated Sep. 23, 2016, pp. 35, for U.S. Appl. No. 14/175,975, filed Feb. 7, 2014.
Information Materials for IDS, Sep. 21, 2018, pp. 1.
Notice of Allowance dated Sep. 12, 2017, pp. 21, for U.S. Appl. No. 14/175,980, filed Feb. 7, 2014.
Office Action dated Aug. 10, 2018, pp. 15, for U.S. Appl. No. 14/263,917.
Office Action dated Aug. 11, 2017, pp. 38, for U.S. Appl. No. 14/175,975, filed Feb. 7, 2014.
Office Action dated Dec. 30, 2015, pp. 36, for U.S. Appl. No. 14/175,964, filed Feb. 7, 2014.
Office Action dated Jul. 21, 2016, pp. 52, for U.S. Appl. No. 14/175,980, filed Feb. 7, 2014.
Office Action dated Mar. 9, 2016, pp. 49, for U.S. Appl. No. 14/175,975, filed Feb. 7, 2014.
Office Action dated May 20, 2016, pp. 52, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Office Action dated Sep. 14, 2017, pp. 41, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Office Action dated Sep. 14, 2017, pp. 48, for U.S. Appl. No. 14/175,964, filed Feb. 7, 2014.
PCT International Search Report and Written Opinion dated Jun. 15, 2015, for Application No. PCT/IB2015/050225, filed Jan. 12, 2015.
PCT International Search Report and Written Opinion dated Sep. 6, 2015 for Application No. PCT/IB2015/052543 filed Apr. 8, 2015, pp. 10.
Pre Appeal Brief dated Jun. 25, 2018 for U.S. Appl. No. 14/175,975, 6 Pgs.
Pre Appeal Brief dated May 21, 2018, for U.S. Appl. No. 14/263,917, 6 Pgs.
Pre-Appeal Brief Request dated Jul. 30, 2018, pp. 6, for U.S. Appl. No. 14/175,964.
Preliminary Amendment dated Jan. 24, 2017, pp. 12, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Response dated Aug. 22, 2016, pp. 17, to Office Action dated May 20, 2016, pp. 52, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Response dated Dec. 14, 2017, pp. 15, to Office Action dated Sep. 14, 2017, pp. 48, for U.S. Appl. No. 14/175,964, filed Feb. 7, 2014.
Response dated Dec. 14, 2017, pp. 17, to Office Action dated Sep. 14, 2017, pp. 41, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Response dated Dec. 20, 2016, pp. 15, to Office Action dated May 20, 2016, pp. 52, for U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
Response dated Jan. 23, 2017, pp. 14, to Final Office Action dated Sep. 23, 2016, pp. 35, for U.S. Appl. No. 14/175,975, filed Feb. 7, 2014.
Response dated Jun. 9, 2016, pp. 14, to Office Action dated Mar. 9, 2016, pp. 49, for U.S. Appl. No. 14/175,975, filed Feb. 7, 2014.
Response dated Mar. 30, 2016, pp. 15, to Office Action dated Dec. 30, 2015, pp. 36, for U.S. Appl. No. 14/175,964, filed Feb. 7, 2014.
Response dated Nov. 13, 2017, pp. 16, to Office Action dated Aug. 11, 2017, pp. 38, for U.S. Appl. No. 14/175,975, filed Feb. 7, 2014.
Response dated Oct. 17, 2016, pp. 14, to Final Office Action dated Jul. 15, 2016, pp. 40, for U.S. Appl. No. 14/175,964, filed Feb. 7, 2014.
Response dated Oct. 21, 2016, pp. 14, for U.S. Appl. No. 14/175,980, filed Feb. 7, 2014.
Robocopy.exe, Microsoft, Corporation, Copyright 1985-2003, pp. 35.
U.S. Appl. No. 14/263,917, filed Apr. 28, 2014.
U.S. Pat. No. 8,666,944 is the English language counterpart of Chinese Patent No. 103262043.
UK Examination Report dated Dec. 16, 2016, pp. 3, for Application No. 1619298.1, filed Apr. 8, 2015.
UK Reply to Examination Report dated Feb. 1, 2017, pp. 13, to UK Examination Report dated Dec. 16, 2016, pp. 3, for Application No. 1619298.1, filed Apr. 8, 2015.
Using a Repository Having a Full Copy of Source Data and Point-In-Time Information From Point-In-Time Copies of the Source Data to Restore the Source Data at Different Points-In-Time, by G.A. Jaquette et al., US Application Serial No. Unknown, filed Feb. 7, 2014.
WO9308529A1 published Apr. 29, 1993, pp. 34, is the English counterpart of CN101149694A.

References: Application No. 2016
 Application No. 2016
 Application No. 201580007367
 Application No. 2016
 Application No. 2016
 Application No. 201580007367
 Application No. 1619298
 Application No. 1619298