Facilitating data consistency in a dispersed storage network
First Claim
1. A method for execution by a processing system of a dispersed storage and task (DST) processing unit that includes a processor, the method comprises:
- determining, via the processor, to access a set of storage units;
identifying, via the processor, an information dispersal algorithm (IDA) width and a decode threshold number included in dispersed storage error encoding parameters associated with the set of storage units;
determining, via the processor, a number of available storage units of the set of storage units;
determining, via the processor, a write threshold number and a read threshold number in accordance with a consistency approach based on the number of available storage units, the IDA width, and the decode threshold number, wherein, when the number of available storage units is determined to be equal to a first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with strong consistency mode dispersal parameters such that the write threshold number is equal to a first write threshold number and the read threshold number is equal to a first read threshold number, and wherein, when the number of available storage units is determined to be equal to a second number that is lower than the first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with impaired mode dispersal parameters such that the write threshold number is equal to a second write threshold number that is lower than the first write threshold number and the read threshold number is equal to a second read threshold number that is lower than the first write threshold number;
issuing, via the processor, the write threshold number of write slice requests to the write threshold number of storage units of the available storage units via a network when the access to the set of storage units includes writing data; and
issuing, via the processor, the read threshold number of read slice requests to the read threshold number of storage units of the available storage units via the network when the access to the set of storage units includes reading data.
3 Assignments
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Accused Products
Abstract
A method for execution by a dispersed storage and task (DST) processing unit that includes a processor includes determining to access a set of storage units; identifying an information dispersal algorithm (IDA) width and a decode threshold number associated with the set of storage units; determining a number of available storage units of the set of storage units; determining a write threshold number and a read threshold number based on the number of available storage units and in accordance with a consistency approach; and accessing at least some of the available storage units utilizing at least one of the write and read threshold numbers.
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Citations
18 Claims
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1. A method for execution by a processing system of a dispersed storage and task (DST) processing unit that includes a processor, the method comprises:
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determining, via the processor, to access a set of storage units; identifying, via the processor, an information dispersal algorithm (IDA) width and a decode threshold number included in dispersed storage error encoding parameters associated with the set of storage units; determining, via the processor, a number of available storage units of the set of storage units; determining, via the processor, a write threshold number and a read threshold number in accordance with a consistency approach based on the number of available storage units, the IDA width, and the decode threshold number, wherein, when the number of available storage units is determined to be equal to a first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with strong consistency mode dispersal parameters such that the write threshold number is equal to a first write threshold number and the read threshold number is equal to a first read threshold number, and wherein, when the number of available storage units is determined to be equal to a second number that is lower than the first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with impaired mode dispersal parameters such that the write threshold number is equal to a second write threshold number that is lower than the first write threshold number and the read threshold number is equal to a second read threshold number that is lower than the first write threshold number; issuing, via the processor, the write threshold number of write slice requests to the write threshold number of storage units of the available storage units via a network when the access to the set of storage units includes writing data; and issuing, via the processor, the read threshold number of read slice requests to the read threshold number of storage units of the available storage units via the network when the access to the set of storage units includes reading data. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A processing system of a dispersed storage and task (DST) processing unit comprises:
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at least one processor; a memory that stores operational instructions, that when executed by the at least one processor cause the processing system to perform operations including; determining, via the processor, to access a set of storage units; identifying, via the processor, an information dispersal algorithm (IDA) width and a decode threshold number included in dispersed storage error encoding parameters associated with the set of storage units; determining, via the processor, a number of available storage units of the set of storage units; determining, via the processor, a write threshold number and a read threshold number in accordance with a consistency approach based on the number of available storage units, the IDA width, and the decode threshold number, wherein, when the number of available storage units is determined to be equal to a first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with strong consistency mode dispersal parameters such that the write threshold number is equal to a first write threshold number and the read threshold number is equal to a first read threshold number, and wherein, when the number of available storage units is determined to be equal to a second number that is lower than the first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with impaired mode dispersal parameters such that the write threshold number is equal to a second write threshold number that is lower than the first write threshold number and the read threshold number is equal to a second read threshold number that is lower than the first write threshold number; issuing, via the processor, the write threshold number of write slice requests to the write threshold number of storage units of the available storage units via a network when the access to the set of storage units includes writing data; and issuing, via the processor, the read threshold number of read slice requests to the read threshold number of storage units of the available storage units via the network when the access to the set of storage units includes reading data. - View Dependent Claims (9, 10, 11, 12, 13, 14)
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15. A non-transitory computer readable storage medium comprises:
at least one memory section that stores operational instructions that, when executed by a processing system of a dispersed storage network (DSN) that includes a processor and a memory, causes the processing system to perform operations including; determining, via the processor, to access a set of storage units; identifying, via the processor, an information dispersal algorithm (IDA) width and a decode threshold number included in dispersed storage error encoding parameters associated with the set of storage units; determining, via the processor, a number of available storage units of the set of storage units; determining, via the processor, a write threshold number and a read threshold number in accordance with a consistency approach based on the number of available storage units, the IDA width, and the decode threshold number, wherein, when the number of available storage units is determined to be equal to a first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with strong consistency mode dispersal parameters such that the write threshold number is equal to a first write threshold number and the read threshold number is equal to a first read threshold number, and wherein, when the number of available storage units is determined to be equal to a second number that is lower than the first number, determining the write threshold number and the read threshold number includes establishing the write threshold number and the read threshold number in accordance with impaired mode dispersal parameters such that the write threshold number is equal to a second write threshold number that is lower than the first write threshold number and the read threshold number is equal to a second read threshold number that is lower than the first write threshold number; issuing, via the processor, the write threshold number of write slice requests to the write threshold number of storage units of the available storage units via a network when the access to the set of storage units includes writing data; and issuing, via the processor, the read threshold number of read slice requests to the read threshold number of storage units of the available storage units via the network when the access to the set of storage units includes reading data. - View Dependent Claims (16, 17, 18)
Specification