25 research outputs found
Partial MDS Codes with Local Regeneration
Partial MDS (PMDS) and sector-disk (SD) codes are classes of erasure codes
that combine locality with strong erasure correction capabilities. We construct
PMDS and SD codes where each local code is a bandwidth-optimal regenerating MDS
code. The constructions require significantly smaller field size than the only
other construction known in literature
Construction of Partial MDS and Sector-Disk Codes With Two Global Parity Symbols
Partial MDS (PMDS) codes are erasure codes combining local (row) correction with global additional correction of entries, while sector-disk (SD) codes are erasure codes that address the mixed failure mode of current redundant arrays of independent disk (RAID) systems. It has been an open problem to construct general codes that have the PMDS and the SD properties, and previous work has relied on Monte-Carlo searches. In this paper, we present a general construction that addresses the case of any number of failed disks and in addition, two erased sectors. The construction requires a modest field size. This result generalizes previous constructions extending RAID 5 and RAID 6
Construction of Partial MDS and Sector-Disk Codes With Two Global Parity Symbols
Partial MDS (PMDS) codes are erasure codes combining local (row) correction with global additional correction of entries, while sector-disk (SD) codes are erasure codes that address the mixed failure mode of current redundant arrays of independent disk (RAID) systems. It has been an open problem to construct general codes that have the PMDS and the SD properties, and previous work has relied on Monte-Carlo searches. In this paper, we present a general construction that addresses the case of any number of failed disks and in addition, two erased sectors. The construction requires a modest field size. This result generalizes previous constructions extending RAID 5 and RAID 6
Maximally Recoverable Codes with Hierarchical Locality
Maximally recoverable codes are a class of codes which recover from all
potentially recoverable erasure patterns given the locality constraints of the
code. In earlier works, these codes have been studied in the context of codes
with locality. The notion of locality has been extended to hierarchical
locality, which allows for locality to gradually increase in levels with the
increase in the number of erasures. We consider the locality constraints
imposed by codes with two-level hierarchical locality and define maximally
recoverable codes with data-local and local hierarchical locality. We derive
certain properties related to their punctured codes and minimum distance. We
give a procedure to construct hierarchical data-local MRCs from hierarchical
local MRCs. We provide a construction of hierarchical local MRCs for all
parameters. For the case of one global parity, we provide a different
construction of hierarchical local MRC over a lower field size.Comment: 6 pages, accepted to National Conference of Communications (NCC) 201