13 research outputs found
On the I/O Costs of Some Repair Schemes for Full-Length Reed-Solomon Codes
Network transfer and disk read are the most time consuming operations in the
repair process for node failures in erasure-code-based distributed storage
systems. Recent developments on Reed-Solomon codes, the most widely used
erasure codes in practical storage systems, have shown that efficient repair
schemes specifically tailored to these codes can significantly reduce the
network bandwidth spent to recover single failures. However, the I/O cost, that
is, the number of disk reads performed in these repair schemes remains largely
unknown. We take the first step to address this gap in the literature by
investigating the I/O costs of some existing repair schemes for full-length
Reed-Solomon codes.Comment: Accepted by the ISIT'1
New Centralized MSR Codes With Small Sub-packetization
Centralized repair refers to repairing node failures using
helper nodes in a centralized way, where the repair bandwidth is counted by the
total amount of data downloaded from the helper nodes. A centralized MSR code
is an MDS array code with -optimal repair for some and . In this
paper, we present several classes of centralized MSR codes with small
sub-packetization. At first, we construct an alternative MSR code with
-optimal repair for multiple repair degrees simultaneously.
Based on the code structure, we are able to construct a centralized MSR code
with -optimal repair property for all possible with
simultaneously. The sub-packetization is no more than , which is much smaller than a previous work given
by Ye and Barg (). Moreover, for general
parameters and , we further give a
centralized MSR code enabling -optimal repair with sub-packetization
smaller than all previous works