Updating data stored in a dispersed storage network

• US 9,262,247 B2
• Filed: 07/15/2014
• Issued: 02/16/2016
• Est. Priority Date: 10/04/2011
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Resch, Jason K., Leggette, Wesley
• Primary Examiner(s): BRITT, CYNTHIA H
• Application Number:
  US14/331,596
• Publication Number:
  US 20140325309A1
• Time in Patent Office: 581 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/00 Error detection; Error correction; Monitoring error detection, correction or monitoring in information storage based on relative movement between record carrier and transducer G11B20/18; monitoring, i.e. supervising the progress of recording or reproducing G11B27/36; in static stores G11C29/00
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/1446 Point-in-time backing up or restoration of persistent data
• CPC Class Codes: G06F 15/17331 Distributed shared memory [DSM], e.g. remote direct memory access [RDMA]
• CPC Class Codes: G06F 21/33 using certificates
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: G06F 3/06 Digital input from, or digital output to, record carriers , e.g. RAID, emulated record carriers or networked record carriers
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• 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 2209/04 Masking or blinding
• CPC Class Codes: H04L 2209/34 Encoding or coding, e.g. Huffman coding or error correction
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 9/085 Secret sharing or secret splitting, e.g. threshold schemes
• CPC Class Codes: H04L 9/0863 involving passwords or one-time passwords network architectures or network communication protocols for using one-time keys in a packet data network H04L63/067
• CPC Class Codes: H04L 9/0869 involving random numbers or seeds
• CPC Class Codes: H04L 9/321 involving a third party or a trusted authority
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823

Abstract

A method begins by a dispersed storage (DS) processing module receiving a modified data object, wherein the modified data object is a modified version of a data object and the data object is divided into a plurality of data segments and stored in the DSN. The method continues with the DS processing module mapping portions of the modified data object to the plurality of data segments that includes creating a middle data segment of a second plurality of data segments based on a corresponding middle data segment of the plurality of data segments when the a portion of the portions corresponds to middle data of the modified data object. The method continues with the DS processing module encoding the middle data segment using a dispersed storage error coding function to produce an encoded data segment and overwriting the corresponding middle data segment with the encoded data segment in the DSN.

Claims

1. A method for execution by a computing device, the method comprises:

identifying a data segment of a plurality of data segments of a data object that is at least partially modified by new data to produce an identified data segment, wherein the new data corresponds to a data difference between a modified data object and the data object, wherein the data object is divided into the plurality of data segments that is encoded using a dispersed storage error coding function to produce a plurality of sets of encoded data slices, wherein the identifying the data segment includes;

segmenting the modified data object based on a segmenting protocol used to segment the data object into the plurality of data segment to produce a modified plurality of data segments;

performing a deterministic function on the data segment to produce a first deterministic value;

identifying a likely corresponding data segment of the modified plurality of data segments to produce an identified corresponding data segment;

performing the deterministic function on the identified corresponding data segment to produce a second deterministic value; and

when the first deterministic value is not substantially equal to the second deterministic value, identifying the data segment;

dispersed storage error encoding the identified data segment to produce a new set of encoded data slices; and

replacing a set of encoded data slices of the plurality of sets of encoded data slices with the new set of encoded data slices to produce a modified plurality of encoded data slices for the modified data object.

2. The method of claim 1 further comprises:

identifying a new data segment of the modified data object;

dispersed storage error encoding the new data segment to produce a second new set of encoded data slices; and

adding the second set of encoded data slices to the modified plurality of encoded data slices for the modified data object.

3. The method of claim 1 further comprises:

segmenting the modified data object based on a segmenting protocol used to segment the data object into the plurality of data segment to produce a modified plurality of data segments;

performing a deterministic function on the plurality of data segments to produce a first plurality of deterministic values;

performing the deterministic function on the modified plurality of data segment to produce a second plurality of deterministic values;

comparing the first plurality of deterministic values to the second plurality of deterministic values; and

when one of the first plurality of first deterministic values substantially matches one of the second plurality of deterministic values, identifying a corresponding data segment as being unmodified.

4. The method of claim 1 further comprises:

updating a segment allocation table of the data object with the data segments corresponding to the modified plurality of encoded data slices.

5. A computer readable storage device comprises:

a first memory section that stores operational instructions that, when executed by a computing device, causes the computing device to;

identify a data segment of a plurality of data segments of a data object that is at least partially modified by new data to produce an identified data segment, wherein the new data corresponds to a data difference between a modified data object and the data object, wherein the data object is divided into the plurality of data segments that is encoded using a dispersed storage error coding function to produce a plurality of sets of encoded data slices, wherein the identifying the data segment includes;

segmenting the modified data object based on a segmenting protocol used to segment the data object into the plurality of data segment to produce a modified plurality of data segments;

performing a deterministic function on the data segment to produce a first deterministic value;

identifying a likely corresponding data segment of the modified plurality of data segments to produce an identified corresponding data segment;

performing the deterministic function on the identified corresponding data segment to produce a second deterministic value; and

when the first deterministic value is not substantially equal to the second deterministic value, identifying the data segment;

a second memory section that stores operational instructions that, when executed by the computing device, causes the computing device to;

dispersed storage error encode the identified data segment to produce a new set of encoded data slices; and

a third memory section that stores operational instructions that, when executed by the computing device, causes the computing device to;

replace a set of encoded data slices of the plurality of sets of encoded data slices with the new set of encoded data slices to produce a modified plurality of encoded data slices for the modified data object.

6. The computer readable storage device of claim 5 further comprises:

the first memory section further stores operational instructions that, when executed by the computing device, causes the computing device to;

identify a new data segment of the modified data object;

the second memory section further stores operational instructions that, when executed by the computing device, causes the computing device to;

dispersed storage error encode the new data segment to produce a second new set of encoded data slices; and

the third memory section further stores operational instructions that, when executed by the computing device, causes the computing device to;

add the second set of encoded data slices to the modified plurality of encoded data slices for the modified data object.

7. The computer readable storage device of claim 5, wherein the first memory section further stores operational instructions that, when executed by the computing device, causes the computing device to:

segment the modified data object based on a segmenting protocol used to segment the data object into the plurality of data segment to produce a modified plurality of data segments;

perform a deterministic function on the plurality of data segments to produce a first plurality of deterministic values;

perform the deterministic function on the modified plurality of data segment to produce a second plurality of deterministic values;

compare the first plurality of deterministic values to the second plurality of deterministic values; and

when one of the first plurality of first deterministic values substantially matches one of the second plurality of deterministic values, identify a corresponding data segment as being unmodified.

8. The computer readable storage device of claim 5, wherein the third memory section further stores operational instructions that, when executed by the computing device, causes the computing device to:

update a segment allocation table of the data object with the data segments corresponding to the modified plurality of encoded data slices.

9. A computer comprises:

an interface;

memory; and

a processing module operably coupled to the interface and the memory, wherein the processing module is operable to;

identify a data segment of a plurality of data segments of a data object that is at least partially modified by new data to produce an identified data segment, wherein the new data corresponds to a data difference between a modified data object and the data object, wherein the data object is divided into the plurality of data segments that is encoded using a dispersed storage error coding function to produce a plurality of sets of encoded data slices, wherein the identifying the data segment includes;

segmenting the modified data object based on a segmenting protocol used to segment the data object into the plurality of data segment to produce a modified plurality of data segments;

performing a deterministic function on the data segment to produce a first deterministic value;

identifying a likely corresponding data segment of the modified plurality of data segments to produce an identified corresponding data segment;

performing the deterministic function on the identified corresponding data segment to produce a second deterministic value; and

when the first deterministic value is not substantially equal to the second deterministic value, identifying the data segment;

dispersed storage error encode the identified data segment to produce a new set of encoded data slices; and

replace, via the interface, a set of encoded data slices of the plurality of sets of encoded data slices with the new set of encoded data slices to produce a modified plurality of encoded data slices for the modified data object.

10. The computer of claim 9, wherein the processing module is further operable to:

identify a new data segment of the modified data object;

dispersed storage error encode the new data segment to produce a second new set of encoded data slices; and

add the second set of encoded data slices to the modified plurality of encoded data slices for the modified data object.

11. The computer of claim 9, wherein the processing module is further operable to:

segment the modified data object based on a segmenting protocol used to segment the data object into the plurality of data segment to produce a modified plurality of data segments;

perform a deterministic function on the plurality of data segments to produce a first plurality of deterministic values;

perform the deterministic function on the modified plurality of data segment to produce a second plurality of deterministic values;

compare the first plurality of deterministic values to the second plurality of deterministic values; and

when one of the first plurality of first deterministic values substantially matches one of the second plurality of deterministic values, identify a corresponding data segment as being unmodified.

12. The computer of claim 9, wherein the processing module is further operable to:

update a segment allocation table of the data object with the data segments corresponding to the modified plurality of encoded data slices.