Utilizing fast memory devices to optimize different functions

• US 10,255,002 B2
• Filed: 11/28/2016
• Issued: 04/09/2019
• Est. Priority Date: 11/30/2015
• Status: Expired due to Fees

• Current Assignee: Pure Storage, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Cabral, Bruno Hennig, Kaczmarek, Joseph M., Khadiwala, Ravi V., Volvovski, Ilya
• Primary Examiner(s): Maskulinski, Michael
• Application Number:
  US15/362,615
• Publication Number:
  US 20170153942A1
• Time in Patent Office: 862 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 11/108 Parity data distribution in semiconductor storages, e.g. in SSD
• CPC Class Codes: G06F 11/1088 Reconstruction on already foreseen single or plurality of spare disks
• CPC Class Codes: G06F 11/1092 Rebuilding, e.g. when physically replacing a failing disk
• CPC Class Codes: G06F 11/1402 Saving, restoring, recovering or retrying
• CPC Class Codes: G06F 11/1464 for networked environments
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 12/0891 using clearing, invalidating or resetting means
• CPC Class Codes: G06F 15/17331 Distributed shared memory [DSM], e.g. remote direct memory access [RDMA]
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 2211/1007 Addressing errors, i.e. silent errors in RAID, e.g. sector slipping and addressing errors
• CPC Class Codes: G06F 2212/1024 Latency reduction
• CPC Class Codes: G06F 2212/154 Networked environment
• CPC Class Codes: G06F 2212/263 Network storage, e.g. SAN or NAS
• CPC Class Codes: G06F 2212/403 Error protection encoding, e.g. using parity or ECC codes
• 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 3/0629 Configuration or reconfiguration of 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 3/0665 : at area level, e.g. provisioning of virtual or logical volumes
• 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 3/0689 : Disk arrays, e.g. RAID, JBOD
• CPC Class Codes: G06F 9/4881 : Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues
• CPC Class Codes: G06F 9/5083 : Techniques for rebalancing the load in a distributed system
• CPC Class Codes: H03M 13/1105 : Decoding
• CPC Class Codes: H03M 13/1515 : Reed-Solomon codes
• CPC Class Codes: H03M 13/3761 : using code combining, i.e. using combining of codeword portions which may have been transmitted separately, e.g. Digital Fountain codes, Raptor codes or Luby Transform [LT] 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: H03M 13/6502 : Reduction of hardware complexity or efficient processing
• CPC Class Codes: H04L 2101/604 : Address structures or formats
• CPC Class Codes: H04L 61/457 : containing identifiers of data entities on a computer, e.g. file names
• CPC Class Codes: H04L 63/101 : Access control lists [ACL]
• 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 computing device includes an interface configured to interface and communicate with a dispersed storage network (DSN), a memory that stores operational instructions, and a processing module operably coupled to the interface and memory such that the processing module, when operable within the computing device based on the operational instructions, is configured to perform various operations. A computing device receives a data access request for an encoded data slice (EDS) associated with a data object. The computing device compares a slice name of the data access request with slice names stored within RAM. When the data access request slice name compares unfavorably with those stored slice names, the computing device transmits an empty data access response that includes no EDS to the other computing device without needing to access a hard disk drive (HDD) that stores EDSs. Alternatively, the computing device transmits a data access response that includes the EDS.

Claims

1. A computing device comprising:

an interface configured to interface and communicate with a dispersed storage network (DSN);

memory that stores operational instructions, wherein the memory includes random access memory (RAM) and a hard disk drive (HDD); and

a processing module operably coupled to the interface and to the memory, wherein the processing module, when operable within the computing device based on the operational instructions, is configured to;

receive from another computing device a data access request for an encoded data slice (EDS) associated with a data object, wherein the data access request includes a data access request slice name for the EDS associated with the data object;

compare the data access request slice name with a plurality of slice names stored within the RAM, wherein the plurality of slice names are respectively associated with a plurality of encoded data slices (EDSs) stored within the HDD;

when the data access request slice name compares unfavorably with the plurality of slice names, transmit an empty data access response that includes no EDS to the another computing device;

when the data access request slice name compares favorably with at least one of the plurality of slice names;

retrieve, from the HDD, an EDS of the plurality of EDSs having a corresponding slice name that compares favorably with the data access request slice name; and

transmit a data access response that includes the EDS of the plurality of EDSs having the corresponding slice name to the another computing device.

2. The computing device of claim 1, wherein the data object is segmented into a plurality of data segments, wherein a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce a set of encoded data slices (EDSs), wherein each EDS of the set of EDS having a respective slice name, wherein the set of EDSs are distributedly stored among a plurality of storage units (SUs) within the DSN, wherein a decode threshold number of EDSs are needed to recover the data segment, wherein a read threshold number of EDSs provides for reconstruction of the data segment, wherein a write threshold number of EDSs provides for a successful transfer of the set of EDSs from a first at least one location in the DSN to a second at least one location in the DSN.

3. The computing device of claim 1, wherein the processing module, when operable within the computing device based on the operational instructions, is further configured to:

compare a revision level for the EDS associated with the data object that is included within the data access request to a plurality of revision levels stored within the RAM, wherein the plurality of revision levels are associated respectively with the plurality of slice names stored within the RAM;

when the data access request slice name compares unfavorably with the plurality of slice names and when the revision level for the EDS associated with the data object compares unfavorably with the plurality of revision levels, transmit the empty data access response to the another computing device;

when the data access request slice name compares favorably with the plurality of slice names and when the revision level for the EDS associated with the data object compares unfavorably with the plurality of revision levels, transmit the empty data access response to the another computing device;

when the data access request slice name compares favorably with at least one of the plurality of slice names and when the revision level for the EDS associated with the data object compares favorably with at least one of the plurality of revision levels;

retrieve, from the HDD, the EDS of the plurality of EDSs having the corresponding slice name that compares favorably with the data access request slice name and a corresponding revision level that compares favorably with the revision level for the EDS associated with the data object; and

transmit the data access response that includes the EDS of the plurality of EDSs having the corresponding slice name and the corresponding revision level that compares favorably with the revision level for the EDS associated with the data object to the another computing device.

4. The computing device of claim 1, wherein the data access request for the EDS associated with the data object is based on at least one of:

a check request involving the EDS associated with the data object;

a read request involving the EDS associated with the data object;

a write request involving the EDS associated with the data object;

a rebuild request involving the EDS associated with the data object;

a rebuild scanning request involving the EDS associated with the data object;

a reallocation request involving the EDS associated with the data object;

a rebalancing request involving the EDS associated with the data object;

a synchronization request between mirrored vault operations involving the EDS associated with the data object;

or

a trimmed write request involving the EDS associated with the data object based on fewer than all of a set of encoded data slices (EDSs) generated when the data object is segmented into a plurality of data segments and a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce the set of EDSs.

5. The computing device of claim 1, wherein the processing module, when operable within the computing device based on the operational instructions, is further configured to:

when the data access request slice name compares unfavorably with the plurality of slice names, generate the empty data access response that includes no EDS without accessing the HDD.

6. The computing device of claim 1 wherein the computing device is located at a first premises that is remotely located from at least one storage unit (SU) of a plurality of storage units (SUs) within the DSN that distributedly store a set of EDSs that includes the EDS associated with the data object.

7. The computing device of claim 1 further comprising:

a storage unit (SU) within the DSN, a wireless smart phone, a laptop, a tablet, a personal computers (PC), a work station, or a video game device.

8. The computing device of claim 1, wherein the DSN includes at least one of a wireless communication system, a wire lined communication systems, a non-public intranet system, a public internet system, a local area network (LAN), or a wide area network (WAN).

9. A computing device comprising:

an interface configured to interface and communicate with a dispersed storage network (DSN);

memory that stores operational instructions, wherein the memory includes random access memory (RAM) and a hard disk drive (HDD); and

a processing module operably coupled to the interface and to the memory, wherein the processing module, when operable within the computing device based on the operational instructions, is configured to;

receive from another computing device a data access request for an encoded data slice (EDS) associated with a data object, wherein the data access request includes a data access request slice name for the EDS associated with the data object, wherein the data object is segmented into a plurality of data segments, wherein a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce a set of encoded data slices (EDSs), wherein each EDS of the set of EDS having a respective slice name, wherein the set of EDSs are distributedly stored among a plurality of storage units (SUs) within the DSN, wherein a decode threshold number of EDSs are needed to recover the data segment, wherein a read threshold number of EDSs provides for reconstruction of the data segment, wherein a write threshold number of EDSs provides for a successful transfer of the set of EDSs from a first at least one location in the DSN to a second at least one location in the DSN;

compare the data access request slice name with a plurality of slice names stored within the RAM, wherein the plurality of slice names are respectively associated with a plurality of encoded data slices (EDSs) stored within the HDD;

when the data access request slice name compares unfavorably with the plurality of slice names;

generate an empty data access response that includes no EDS without accessing the HDD; and

transmit the empty data access response that includes no EDS to the another computing device;

when the data access request slice name compares favorably with at least one of the plurality of slice names;

retrieve, from the HDD, an EDS of the plurality of EDSs having a corresponding slice name that compares favorably with the data access request slice name; and

transmit a data access response that includes the EDS of the plurality of EDSs having the corresponding slice name to the another computing device.

10. The computing device of claim 9, wherein the processing module, when operable within the computing device based on the operational instructions, is further configured to:

compare a revision level for the EDS associated with the data object that is included within the data access request to a plurality of revision levels stored within the RAM, wherein the plurality of revision levels are associated respectively with the plurality of slice names stored within the RAM;

when the data access request slice name compares unfavorably with the plurality of slice names and when the revision level for the EDS associated with the data object compares unfavorably with the plurality of revision levels, transmit the empty data access response to the another computing device;

when the data access request slice name compares favorably with the plurality of slice names and when the revision level for the EDS associated with the data object compares unfavorably with the plurality of revision levels, transmit the empty data access response to the another computing device;

when the data access request slice name compares favorably with at least one of the plurality of slice names and when the revision level for the EDS associated with the data object compares favorably with at least one of the plurality of revision levels;

retrieve, from the HDD, the EDS of the plurality of EDSs having the corresponding slice name that compares favorably with the data access request slice name and a corresponding revision level that compares favorably with the revision level for the EDS associated with the data object; and

transmit the data access response that includes the EDS of the plurality of EDSs having the corresponding slice name and the corresponding revision level that compares favorably with the revision level for the EDS associated with the data object to the another computing device.

11. The computing device of claim 9, wherein the data access request for the EDS associated with the data object is based on at least one of:

a check request involving the EDS associated with the data object;

a read request involving the EDS associated with the data object;

a write request involving the EDS associated with the data object;

a rebuild request involving the EDS associated with the data object;

a rebuild scanning request involving the EDS associated with the data object;

a reallocation request involving the EDS associated with the data object;

a rebalancing request involving the EDS associated with the data object;

a synchronization request between mirrored vault operations involving the EDS associated with the data object;

or

a trimmed write request involving the EDS associated with the data object based on fewer than all of a set of encoded data slices (EDSs) generated when the data object is segmented into a plurality of data segments and a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce the set of EDSs.

12. The computing device of claim 9 further comprising:

a SU of the plurality of SUs within the DSN, a wireless smart phone, a laptop, a tablet, a personal computers (PC), a work station, or a video game device.

13. The computing device of claim 9, wherein the DSN includes at least one of a wireless communication system, a wire lined communication systems, a non-public intranet system, a public internet system, a local area network (LAN), or a wide area network (WAN).

14. A method for execution by a computing device, the method comprising:

receiving, via an interface configured to interface and communicate with a dispersed storage network (DSN), from another computing device a data access request for an encoded data slice (EDS) associated with a data object, wherein the data access request includes a data access request slice name for the EDS associated with the data object;

comparing the data access request slice name with a plurality of slice names stored within random access memory (RAM) of the computing device, wherein the plurality of slice names are respectively associated with a plurality of encoded data slices (EDSs) stored within the HDD;

when the data access request slice name compares unfavorably with the plurality of slice names, transmitting via the interface an empty data access response that includes no EDS to the another computing device;

when the data access request slice name compares favorably with at least one of the plurality of slice names;

retrieving, from an hard disk drive (HDD) of the computing device, an EDS of the plurality of EDSs having a corresponding slice name that compares favorably with the data access request slice name; and

transmitting via the interface a data access response that includes the EDS of the plurality of EDSs having the corresponding slice name to the another computing device.

15. The method of claim 14, wherein the data object is segmented into a plurality of data segments, wherein a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce a set of encoded data slices (EDSs), wherein each EDS of the set of EDS having a respective slice name, wherein the set of EDSs are distributedly stored among a plurality of storage units (SUs) within the DSN, wherein a decode threshold number of EDSs are needed to recover the data segment, wherein a read threshold number of EDSs provides for reconstruction of the data segment, wherein a write threshold number of EDSs provides for a successful transfer of the set of EDSs from a first at least one location in the DSN to a second at least one location in the USN.

16. The method of claim 14 further comprising:

comparing a revision level for the EDS associated with the data object that is included within the data access request to a plurality of revision levels stored within the RAM, wherein the plurality of revision levels are associated respectively with the plurality of slice names stored within the RAM;

when the data access request slice name compares unfavorably with the plurality of slice names and when the revision level for the EDS associated with the data object compares unfavorably with the plurality of revision levels, transmitting via the interface the empty data access response to the another computing device;

when the data access request slice name compares favorably with the plurality of slice names and when the revision level for the EDS associated with the data object compares unfavorably with the plurality of revision levels, transmitting via the interface the empty data access response to the another computing device;

when the data access request slice name compares favorably with at least one of the plurality of slice names and when the revision level for the EDS associated with the data object compares favorably with at least one of the plurality of revision levels;

retrieving, from the HDD, the EDS of the plurality of EDSs having the corresponding slice name that compares favorably with the data access request slice name and a corresponding revision level that compares favorably with the revision level for the EDS associated with the data object; and

transmitting via the interface the data access response that includes the EDS of the plurality of EDSs having the corresponding slice name and the corresponding revision level that compares favorably with the revision level for the EDS associated with the data object to the another computing device.

17. The method of claim 14, wherein the data access request for the EDS associated with the data object is based on at least one of:

a check request involving the EDS associated with the data object;

a read request involving the EDS associated with the data object;

a write request involving the EDS associated with the data object;

a rebuild request involving the EDS associated with the data object;

a rebuild scanning request involving the EDS associated with the data object;

a reallocation request involving the EDS associated with the data object;

a rebalancing request involving the EDS associated with the data object;

a synchronization request between mirrored vault operations involving the EDS associated with the data object;

or

a trimmed write request involving the EDS associated with the data object based on fewer than all of a set of encoded data slices (EDSs) generated when the data object is segmented into a plurality of data segments and a data segment of the plurality of data segments is dispersed error encoded in accordance with dispersed error encoding parameters to produce the set of EDSs.

18. The method of claim 14 further comprising:

when the data access request slice name compares unfavorably with the plurality of slice names, generating the empty data access response that includes no EDS without accessing the HDD.

19. The method of claim 14, wherein the computing device includes a storage unit (SU) within the DSN, a wireless smart phone, a laptop, a tablet, a personal computers (PC), a work station, or a video game device.

20. The method of claim 14, wherein the DSN includes at least one of a wireless communication system, a wire lined communication systems, a non-public intranet system, a public Internet system, a local area network (LAN), or a wide area network (WAN).