Selection of erasure code parameters for no data repair

摘要

An improved data storage technique achieves a desired level of reliability by providing sufficient redundancy in erasure coded data to maintain the data, without repair, for a prescribed period of time. The improved technique employs a newly devised, continuous-time Markov chain model. The model can be applied in computerized systems to establish erasure coding parameters for storing and reliably maintaining data for a designated period of time, without any need to repair the data to reestablish an original or previous level of erasure coding redundancy.

主权项

1. A method of managing storage of a set of data for a desired retention period, comprising:
calculating, by a set of processors executing instructions stored in memory of a computerized apparatus, a mean time to data loss (MTTDL) of a chunk of the set of data by applying a pair of erasure coding parameters, N and K, in an equation for MTTDL, wherein N represents a total number of fragments for storing the chunk and K represents a minimum number of the N fragments that are needed to ensure that the chunk can be recovered without data loss; selecting, in response to the calculated MTTDL being at least as great as the desired retention period, erasure coding parameters N′ and K′ for performing an erasure coding operation on the chunk; storing the chunk in memory of a computing node distinct the computerized apparatus; and performing, by a set of processors of the computing node, an erasure coding operation on the chunk using erasure coding parameters N′ and K′, wherein N′ is at least as great as N, and wherein K′ is at least as great as K.