Apportioning storage units amongst storage sites in a dispersed storage network

• US 10,169,148 B2
• Filed: 08/18/2016
• Issued: 01/01/2019
• Est. Priority Date: 03/29/2016
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Resch, Jason K.
• Primary Examiner(s): Krofcheck, Michael
• Application Number:
  US15/240,591
• Publication Number:
  US 20170285993A1
• Time in Patent Office: 866 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 11/1092 Rebuilding, e.g. when physically replacing a failing disk
• CPC Class Codes: G06F 11/1662 the resynchronized component or unit being a persistent storage device re-synchronization of failed mirror storage G06F11/2082; rebuild or reconstruction of parity RAID storage G06F11/1008
• CPC Class Codes: G06F 11/3034 where the computing system component is a storage system, e.g. DASD based or network based digital input from or digital output to record carriers G06F3/06; digital recording or reproducing G11B20/18; 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], H04L67/1097
• CPC Class Codes: G06F 11/3051 Monitoring arrangements for monitoring the configuration of the computing system or of the computing system component, e.g. monitoring the presence of processing resources, peripherals, I/O links, software programs verification or detection of system hardware configuration G06F11/2247
• CPC Class Codes: G06F 11/3684 for test design, e.g. generating new test cases
• CPC Class Codes: G06F 11/3688 for test execution, e.g. scheduling of test suites
• CPC Class Codes: G06F 11/3692 for test results analysis
• CPC Class Codes: G06F 2201/805 Real-time
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• 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 3/0631 by allocating resources to storage systems
• 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 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0653 Monitoring storage devices or systems
• 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: H03M 13/1515 : Reed-Solomon codes
• CPC Class Codes: H03M 13/373 : with erasure correction and erasure determination, e.g. for packet loss recovery or setting of erasures for the decoding of Reed-Solomon codes
• CPC Class Codes: H03M 13/616 : Matrix operations, especially for generator matrices or check matrices, e.g. column or row permutations
• 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]

Abstract

A method of apportioning storage units in a dispersed storage network (DSN) includes generating storage unit apportioning data indicating a mapping of a plurality of desired numbers of storage units to a plurality of storage sites based on site reliability data. The mapping includes a first desired number of storage units corresponding to a first one of the plurality of storage sites that is greater than a second desired number of storage units corresponding to a second one of the plurality of storage sites in response to the site reliability data indicating that a first reliability score corresponding to the first one of the plurality of storage sites is more favorable than a second reliability score corresponding to the second one of the plurality of storage sites. A plurality of storage units are allocated to the plurality of storage sites based on the storage unit apportioning data.

Claims

1. A method of apportioning storage units in a dispersed storage network (DSN), the method comprising:

generating storage unit apportioning data indicating a mapping of a plurality of desired numbers of storage units, represented as a plurality of numerical values in accordance with the plurality of desired numbers, to a plurality of storage sites based on site reliability data, wherein the mapping includes a first desired number of storage units corresponding to a first one of the plurality of storage sites that is greater than a second desired number of storage units corresponding to a second one of the plurality of storage sites in response to the site reliability data indicating that a first reliability score corresponding to the first one of the plurality of storage sites is more favorable than a second reliability score corresponding to the second one of the plurality of storage sites; and

allocating a plurality of storage units to the plurality of storage sites based on the storage unit apportioning data, wherein each of the plurality of storage units includes at least one processor and at least one memory device.

2. The method of claim 1, wherein the plurality of desired numbers of storage units of the mapping are proportional to a corresponding plurality of reliability scores of the plurality of storage sites indicated by the site reliability data, wherein the corresponding plurality of reliability scores includes the first reliability score and the second reliability score.

3. The method of claim 1, wherein generating the storage unit apportioning data further indicates a storage unit total that is based on at least one of:

a write threshold or a read threshold, and wherein the sum of the plurality of desired numbers of storage units is equal to the storage unit total.

4. The method of claim 1, wherein the site reliability data is based on a plurality of reliability readings originating from each of the plurality of storage sites.

5. The method of claim 1, wherein the plurality of storage sites are located in a plurality of different physical locations, and wherein the site reliability data is based on geographical data associated with each of the plurality of different physical locations.

6. The method of claim 1, further comprising generating the site reliability data based on site history data indicating past performance metrics for the plurality of storage sites.

7. The method of claim 6, wherein the site history data includes past outages of each of the plurality of storage sites.

8. The method of claim 1, wherein the storage unit apportioning data includes optimal performance data, wherein the first desired number of storage units is set to a first optimal value and the second desired number of storage units is set to a second optimal value in response to the optimal performance data indicating that selecting the first optimal value and the second optimal value maximizes at least one of:

read availability, write availability, rebuilding cost, or access performance.

9. The method of claim 1, wherein the site reliability data indicates a plurality of reliability scores corresponding to the plurality of storage sites, and wherein the storage unit apportioning data indicates the same desired number of storage units for each of the plurality of storage sites in response to the plurality of reliability scores having the same value.

10. The method of claim 1, further comprising:

generating reassignment data in response to a change in the site reliability data, wherein the reassignment data indicates a new mapping of a new plurality of desired numbers of storage units to the plurality of storage sites based on the change in the site reliability data; and

reallocating the plurality of storage units to the plurality of storage sites based on the reassignment data.

11. A dispersed storage network (DSN) comprises:

a plurality of storage sites; and

a plurality of storage units, apportioned amongst the plurality of storage sites, wherein the plurality of storage units are apportioned by;

generating storage unit apportioning data indicating a mapping of a plurality of desired numbers of storage units, represented as a plurality of numerical values in accordance with the plurality of desired numbers, to a plurality of storage sites based on site reliability data, wherein the mapping includes a first desired number of storage units corresponding to a first one of the plurality of storage sites that is greater than a second desired number of storage units corresponding to a second one of the plurality of storage sites in response to the site reliability data indicating that a first reliability score corresponding to the first one of the plurality of storage sites is more favorable than a second reliability score corresponding to the second one of the plurality of storage sites; and

allocating a plurality of storage units to the plurality of storage sites based on the storage unit apportioning data, wherein each of the plurality of storage units includes at least one processor and at least one memory device.

12. The DSN of claim 11, wherein the plurality of desired numbers of storage units of the mapping are proportional to a corresponding plurality of reliability scores of the plurality of storage sites indicated by the site reliability data, wherein the corresponding plurality of reliability scores includes the first reliability score and the second reliability score.

13. The DSN of claim 11, wherein generating the storage unit apportioning data further indicates a storage unit total that is based on at least one of:

a write threshold or a read threshold, and wherein the sum of the plurality of desired numbers is equal to the storage unit total.

14. The DSN of claim 11, wherein the site reliability data is based on a plurality of reliability readings originating from each of the plurality of storage sites.

15. The DSN of claim 11, wherein the plurality of storage sites are located in a plurality of different physical locations, and wherein the site reliability data is based on geographical data associated with each of the plurality of different physical locations.

16. The DSN of claim 11, wherein apportioning the plurality of storage units further includes generating the site reliability data based on site history data indicating past performance metrics for the plurality of storage sites.

17. The DSN of claim 16, wherein the site history data includes past outages of each of the plurality of storage sites.

18. The DSN of claim 11, wherein the storage unit apportioning data includes optimal performance data, wherein the first desired number of storage units is set to a first optimal value and the second desired number of storage units is set to a second optimal value in response to the optimal performance data indicating that selecting the first optimal value and the second optimal value maximizes at least one of:

read availability, write availability, rebuilding cost, or access performance.

19. The DSN of claim 11, wherein the site reliability data indicates a plurality of reliability scores corresponding to the plurality of storage sites, and wherein the storage unit apportioning data indicates the same desired number of storage units for each of the plurality of storage sites in response to the plurality of reliability scores having the same value.

20. The DSN of claim 11, wherein apportioning the plurality of storage units further includes:

generating reassignment data in response to a change in the site reliability data, wherein the reassignment data indicates a new mapping of a new plurality of desired numbers of storage units to the plurality of storage sites based on the change in the site reliability data; and

reallocating the plurality of storage units to the plurality of storage sites based on the reassignment data.