Selecting storage units in one or more dispersed storage networks

• US 10,027,755 B2
• Filed: 06/01/2016
• Issued: 07/17/2018
• Est. Priority Date: 06/01/2016
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Ober, Brian F., Resch, Jason K.
• Primary Examiner(s): Bui, Jonathan A
• Application Number:
  US15/170,675
• Publication Number:
  US 20170353552A1
• Time in Patent Office: 776 Days
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 16/1824 implemented using Network-attached Storage [NAS] architecture distributed or networked storage systems G06F3/067; protocols for distributed storage of data in a network H04L67/1097
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal

Abstract

A method includes identifying a data access issue between a computing device and a first set of storage units regarding a data object. The method further includes determining whether the computing device will have a lessened data access issue with a second set of storage units. The method further includes, when the computing device will have the lessened data access issue with the second set of storage units, sending a copy of a transfer number of encoded data slices for each set of a plurality of sets of encoded data slices from at least some of the storage units of the first set of storage units to at least some of the storage units of the second set of storage units. The method further includes establishing access for the computing device to access the second set of storage units regarding the data object.

Claims

1. A method for execution by one or more processing modules of one or more dispersed storage networks (DSN) of a plurality of DSNs, the method comprises:

identifying a data access issue between a computing device and a first set of storage units regarding a data object;

determining whether the computing device will have a lessened data access issue with a second set of storage units;

when the computing device will have the lessened data access issue with the second set of storage units, sending a copy of a transfer number of encoded data slices for each set of a plurality of sets of encoded data slices from at least some of the storage units of the first set of storage units to at least some of the storage units of the second set of storage units, wherein the data object is divided into a plurality of data segments, wherein a data segment of the plurality of data segments is dispersed storage error encoded into a set of encoded data slices, wherein a decode threshold number of encoded data slices of the set of encoded data slices is needed to recover the data segment, and wherein the transfer number is equal or greater than the decode threshold number and less than a total number of encoded data slices in the set of encoded data slices; and

establishing access for the computing device to access the second set of storage units regarding the data object.

2. The method of claim 1 further comprises:

the first set of storage units is associated with a first DSN; and

the second set of storage units is associated with a second DSN, wherein the first and second DSNs have a cooperative relationship regarding data access.

3. The method of claim 1, wherein the determining whether the computing device will have the lessened data access issue with the second set of storage units comprises:

determining a geographic location of the computing device; and

when the geographic location of the computing device is significantly closer to the second set of storage units than to the first set of storage units, determining that the computing device will have the lessened data access issue with the second set of storage units.

4. The method of claim 1, wherein the determining whether the computing device will have the lessened data access issue with the second set of storage units comprises:

receiving a data access request from the computing device;

determining a first processing cycle time with respect to the first set of storage units;

determining a second processing cycle time with respect to the second set of storage units; and

when the second process cycle time is at least a cycle time threshold less than the first processing cycle time, determining that the computing device will have the lessened data access issue with the second set of storage units.

5. The method of claim 1, wherein the determining whether the computing device will have the lessened data access issue with the second set of storage units comprises:

receiving a request message that the computing device is, or will be, roaming to a geographic region primarily supported by the second set of storage units and access to the second set of storage units is requested for the computing device.

6. The method of claim 1 further comprises:

identifying, by a first processing module of a first DSN of the plurality of DSNs, the data access issue, wherein the first set of storage units is affiliated with the first DSN;

determining, by at least one of the first processing module and a second processing module of a second DSN of the plurality of DSNs, whether the computing device will have the lessened data access issue, wherein the second set of storage units is affiliated with the second DSN;

when the computing device will have the lessened data access issue with the second set of storage units, issuing a request, by the second processing module, for the sending of the copy of the transfer number of encoded data slices for each set of the plurality of sets of encoded data slices from at least some of the storage units of the first set of storage units; and

establishing, by the second processing module, the access for the computing device to access the second set of storage units regarding the data object.

7. The method of claim 1, wherein the identifying the data access issue and the determining the lessened data access issue comprises:

receiving a request by the computing device to access the data object via the second set of storage units.

8. The method of claim 1 further comprises:

processing a data access request of the computing device for the data object via the second set of storage units;

when the data access request is a write request, storing an edited plurality of sets of encoded data slices of the data object within the second set of storage units, wherein each set of the edited plurality of sets includes the total number of encoded data slices; and

when the computing device will have the lessened data access issue with the first set of storage units with respect to the second set of storage units, transferring the edited plurality of sets of encoded data slices from the second set of storage units to the first set of storage units.

9. A computer readable memory device comprises:

a first memory component that stores operational instructions that, when executed by one or more processing modules of one or more dispersed storage networks (DSN) of a plurality of DSNs, causes the one or more processing modules to;

identify a data access issue between a computing device and a first set of storage units regarding a data object; and

determine whether the computing device will have a lessened data access issue with a second set of storage units;

a second memory component that stores operational instructions that, when executed by the one or more processing modules, causes the one or more processing modules to;

when the computing device will have the lessened data access issue with the second set of storage units, send a copy of a transfer number of encoded data slices for each set of a plurality of sets of encoded data slices from at least some of the storage units of the first set of storage units to at least some of the storage units of the second set of storage units, wherein the data object is divided into a plurality of data segments, wherein a data segment of the plurality of data segments is dispersed storage error encoded into a set of encoded data slices, wherein a decode threshold number of encoded data slices of the set of encoded data slices is needed to recover the data segment, and wherein the transfer number is equal or greater than the decode threshold number and less than a total number of encoded data slices in the set of encoded data slices; and

a third memory component that stores operational instructions that, when executed by the one or more processing modules, causes the one or more processing modules to;

establish access for the computing device to access the second set of storage units regarding the data object.

10. The computer readable memory device of claim 9 further comprises:

the first set of storage units is associated with a first DSN; and

the second set of storage units is associated with a second DSN, wherein the first and second DSNs have a cooperative relationship regarding data access.

11. The computer readable memory device of claim 9, wherein the first memory component further stores operational instructions that, when executed by the one or more processing modules, causes the one or more processing modules to determine whether the computing device will have the lessened data access issue with the second set of storage units by:

determining a geographic location of the computing device; and

when the geographic location of the computing device is significantly closer to the second set of storage units than to the first set of storage units, determining that the computing device will have the lessened data access issue with the second set of storage units.

12. The computer readable memory device of claim 9, wherein the first memory component further stores operational instructions that, when executed by the one or more processing modules, causes the one or more processing modules to determine whether the computing device will have the lessened data access issue with the second set of storage units by:

receiving a data access request from the computing device;

determining a first processing cycle time with respect to the first set of storage units;

determining a second processing cycle time with respect to the second set of storage units; and

when the second process cycle time is at least a cycle time threshold less than the first processing cycle time, determining that the computing device will have the lessened data access issue with the second set of storage units.

13. The computer readable memory device of claim 9, wherein the first memory component further stores operational instructions that, when executed by the one or more processing modules, causes the one or more processing modules to determine whether the computing device will have the lessened data access issue with the second set of storage units by:

receiving a request message that the computing device is, or will be, roaming to a geographic region primarily supported by the second set of storage units and access to the second set of storage units is requested for the computing device.

14. The computer readable memory device of claim 9, wherein the first memory component further stores operational instructions that, when executed by the one or more processing modules, causes the one or more processing modules to identify the data access issue and to determine the lessened data access issue by:

receiving a request by the computing device to access the data object via the second set of storage units.

15. The computer readable memory device of claim 9 further comprises:

a third memory component that stores operational instructions that, when executed by the one or more processing modules, causes the one or more processing modules to;

process a data access request of the computing device for the data object via the second set of storage units;

when the data access request is a write request, store an edited plurality of sets of encoded data slices of the data object within the second set of storage units, wherein each set of the edited plurality of sets includes the total number of encoded data slices; and

when the computing device will have the lessened data access issue with the first set of storage units than with respect to the second set of storage units, transfer the edited plurality of sets of encoded data slices from the second set of storage units to the first set of storage units.