Accessing a dispersed storage network

• US 10,225,205 B2
• Filed: 02/23/2018
• Issued: 03/05/2019
• Est. Priority Date: 06/30/2014
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Resch, Jason K., Dhuse, Greg, Motwani, Manish, Baptist, Andrew, Leggette, Wesley, Khadiwala, Ravi
• Primary Examiner(s): Nguyen, Phuoc H
• Application Number:
  US15/903,992
• Publication Number:
  US 20180191633A1
• Time in Patent Office: 375 Days
• Field of Search: 709212-216
• CPC Class Codes: G06F 3/0616 in relation to life time, e.g. increasing Mean Time Between Failures [MTBF]
• CPC Class Codes: G06F 3/0623 in relation to content
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0685 Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• 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

Methods and apparatus for selection of memory locations for data access operations in a dispersed storage network (DSN) are disclosed. In various embodiments, a dispersed storage (DS) processing module of the DSN receives a DSN access request regarding at least one data segment of a data object. The DS processing module determines a DSN address associated with the DSN access request and performs a scoring function using the DSN address and one or more properties of DSN memory to produce a storage scoring resultant. The storage scoring resultant is utilized to identify a set of storage units of the DSN. A set of access requests is then sent to the set of storage units regarding the DSN access request. The scoring function can include, for example, performing deterministic functions, normalizing functions and ranking functions to produce the storage scoring resultant.

Claims

1. A method for execution by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), the method comprises:

receiving a DSN access request regarding at least one data segment of a data object associated with the DSN;

determining a DSN address associated with the DSN access request;

performing a scoring function using the DSN address and one or more properties of DSN memory of the DSN to produce a storage scoring resultant, wherein the DSN memory includes a plurality of storage units;

utilizing the storage scoring resultant to identify a set of storage units of the plurality of storage units; and

sending a set of access requests to the set of storage units regarding the DSN access request.

2. The method of claim 1, wherein the DSN address includes at least one of a source name, a data segment identifier (ID) of the at least one data segment, a set of slice names associated with the at least one data segment, or a plurality of sets of slice names associated with a plurality of sets of encoded data slices associated with storage of the data object.

3. The method of claim 2, wherein the source name includes at least one of a vault identifier or an object number associated with a data name of the data object.

4. The method of claim 1, wherein the DSN access request includes at least one of a store data request, a retrieve data request, a delete data request, a data name, or a requesting entity identifier.

5. The method of claim 1 further comprises:

when the storage scoring resultant identifies a pillar width number of storage units, utilizing one or more properties of storage units in the pillar width number of storage units to identify at least a decode threshold number of storage units; and

using the at least a decode threshold number of storage units as the set of storage units.

6. The method of claim 1 further comprises:

when the storage scoring resultant identifies particular memory devices within storage units of the plurality of storage units, utilizing one or more properties of storage units in a pillar width number of storage units to identify at least a decode threshold number of storage units;

utilizing one or more properties of memory devices within storage units of the at least a decode threshold number of storage units to identify the set of storage units; and

wherein the set of access requests includes indications of particular memory devices within the set of storage units, and wherein the indications of particular memory devices are based on the one or more properties of memory devices.

7. The method of claim 1, wherein the performing the scoring function further comprises:

selecting a resource level relating to the DSN memory;

selecting the one or more properties of DSN memory from a plurality of properties of the DSN memory based on the selected resource level;

calculating, based on the selected resource level, a plurality of storage values based on the DSN address and the one or more properties of DSN memory; and

performing a ranking function of the plurality of storage values to produce the storage scoring resultant.

8. The method of claim 1, wherein the plurality of storage units of the DSN memory are logically arranged as a plurality of storage pools, and wherein the performing the scoring function further comprises:

selecting a storage pool level indication as a resource level;

selecting a storage pool identifier and a storage pool weighting factor for each of the plurality of storage pools to produce a plurality of storage pool identifiers and a plurality of storage pool weighting factors, wherein the one or more properties of DSN memory includes the plurality of storage pool identifiers and the plurality of storage pool weighting factors;

performing a series of functions on the DSN address based on the plurality of storage pool identifiers and the plurality of storage pool weighting factors to produce a plurality of storage values; and

performing a ranking function of the plurality of storage values to produce the storage scoring resultant.

9. The method of claim 8, wherein a series of the series of functions comprises:

a deterministic function of the DSN address and one of the plurality of storage pool identifiers to produce an interim result;

a normalizing function of the interim result to produce a normalized interim result; and

a scoring function of the normalized interim result and a corresponding one of the plurality of storage pool weighting factors to produce a storage value of the plurality of storage values.

10. The method of claim 1, wherein the performing the scoring function further comprises:

selecting a storage unit level indication as a resource level;

selecting a storage site-storage unit identifier and a storage site-storage weighting factor for each of the plurality of storage units to produce a plurality of storage site-storage unit identifiers and a plurality of storage site-storage unit weighting factors, wherein the one or more properties of DSN memory includes the plurality of storage site-storage unit identifiers and the plurality of storage site-storage unit weighting factors;

performing a series of functions on the DSN address based on the plurality of storage site-storage unit identifiers and the plurality of storage site-storage unit weighting factors to produce a plurality of storage values; and

performing a ranking function of the plurality of storage values to produce the storage scoring resultant.

11. A computer readable storage medium comprises:

at least one memory section that stores operational instructions that, when executed by one or more processing modules of one or more computing devices of a dispersed storage network (DSN), causes the one or more computing devices to;

receive a DSN access request regarding at least one data segment of a data object associated with the DSN;

determine a DSN address associated with the DSN access request;

perform a scoring function using the DSN address and one or more properties of DSN memory of the DSN to produce a storage scoring resultant, wherein the DSN memory includes a plurality of storage units;

utilize the storage scoring resultant to identify a set of storage units of the plurality of storage units; and

send a set of access requests to the set of storage units regarding the DSN access request.

12. The computer readable storage medium of claim 11, wherein the DSN address includes at least one of a source name, a data segment identifier (ID) of the at least one data segment, a set of slice names associated with the at least one data segment, or a plurality of sets of slice names associated with a plurality of sets of encoded data slices associated with storage of the data object.

13. The computer readable storage medium of claim 11 further comprises:

the at least one memory section stores further operational instructions that, when executed by the one or more processing modules, causes the one or more computing devices of the DSN to;

when the storage scoring resultant identifies a pillar width number of storage units, utilize one or more properties of storage units in the pillar width number of storage units to identify at least a decode threshold number of storage units; and

use the at least a decode threshold number of storage units as the set of storage units.

14. The computer readable storage medium of claim 11 further comprises:

the at least one memory section stores further operational instructions that, when executed by the one or more processing modules, causes the one or more computing devices of the DSN to;

when the storage scoring resultant identifies particular memory devices within storage units of the plurality of storage units, utilize one or more properties of storage units in a pillar width number of storage units to identify at least a decode threshold number of storage units;

utilize one or more properties of memory devices within storage units of the at least a decode threshold number of storage units to identify the set of storage units; and

wherein the set of access requests includes indications of particular memory devices within the set of storage units, and wherein the indications of particular memory devices are based on the one or more properties of memory devices.

15. The computer readable storage medium of claim 11, wherein the one or more processing modules functions to execute the operational instructions stored by the at least one memory section to cause the one or more computing devices of the DSN to further perform the scoring function by:

selecting a resource level relating to the DSN memory;

selecting the one or more properties of DSN memory from a plurality of properties of the DSN memory based on the selected resource level;

calculating, based on the selected resource level, a plurality of storage values based on the DSN address and the one or more properties of DSN memory; and

performing a ranking function of the plurality of storage values to produce the storage scoring resultant.

16. The computer readable storage medium of claim 11, wherein the plurality of storage units of the DSN memory are logically arranged as a plurality of storage pools, and wherein the one or more processing modules functions to execute the operational instructions stored by the at least one memory section to cause the one or more computing devices of the DSN to further perform the scoring function by:

selecting a storage pool level indication as a resource level;

selecting a storage pool identifier and a storage pool weighting factor for each of the plurality of storage pools to produce a plurality of storage pool identifiers and a plurality of storage pool weighting factors, wherein the one or more properties of DSN memory includes the plurality of storage pool identifiers and the plurality of storage pool weighting factors;

performing a series of functions on the DSN address based on the plurality of storage pool identifiers and the plurality of storage pool weighting factors to produce a plurality of storage values; and

performing a ranking function of the plurality of storage values to produce the storage scoring resultant.

17. The computer readable storage medium of claim 16, wherein a series of the series of functions comprises:

a deterministic function of the DSN address and one of the plurality of storage pool identifiers to produce an interim result;

a normalizing function of the interim result to produce a normalized interim result; and

a scoring function of the normalized interim result and a corresponding one of the plurality of storage pool weighting factors to produce a storage value of the plurality of storage values.

18. The computer readable storage medium of claim 11, wherein the one or more processing modules functions to execute the operational instructions stored by the at least one memory section to cause the one or more computing devices of the DSN to further perform the scoring function by:

selecting a storage unit level indication as a resource level;

selecting a storage site-storage unit identifier and a storage site-storage weighting factor for each of the plurality of storage units to produce a plurality of storage site-storage unit identifiers and a plurality of storage site-storage unit weighting factors, wherein the one or more properties of DSN memory includes the plurality of storage site-storage unit identifiers and the plurality of storage site-storage unit weighting factors;

performing a series of functions on the DSN address based on the plurality of storage site-storage unit identifiers and the plurality of storage site-storage unit weighting factors to produce a plurality of storage values; and

performing a ranking function of the plurality of storage values to produce the storage scoring resultant.

19. A computing device of a group of computing devices of a dispersed storage network (DSN), the computing device comprises:

an interface;

a local memory comprising instructions; and

a processing module operably coupled to the interface and the local memory, wherein the processing module executes the instructions to;

receive, via the interface, a DSN access request regarding at least one data segment of a data object associated with the DSN;

determine a DSN address associated with the DSN access request;

perform a scoring function using the DSN address and one or more properties of DSN memory of the DSN to produce a storage scoring resultant, wherein the DSN memory includes a plurality of storage units;

utilize the storage scoring resultant to identify a set of storage units of the plurality of storage units; and

send, via the interface, a set of access requests to the set of storage units regarding the DSN access request.

20. The computing device of claim 19, wherein the processing module further executes the instructions to:

select a resource level relating to the DSN memory;

select the one or more properties of DSN memory from a plurality of properties of the DSN memory based on the selected resource level;

calculate, based on the selected resource level, a plurality of storage values based on the DSN address and the one or more properties of DSN memory; and

perform a ranking function of the plurality of storage values to produce the storage scoring resultant.