Ceph

Coupled Layer (CL) Code is an MDS code that uses optimal repair bandwidth, disk bandwidth during a node repair.
This code was constructed in https://arxiv.org/abs/1607.07335

It is defined by parameters (k,m,d), k data chunks are encoded to get m parity chunks. This code can recover from loss of any m chunks out of the k+m chunks. During repair, d repair chunks will be used where each repair chunk is a fraction of the complete chunk.

How to Use: ceph osd erasure-code-profile set cl_msr_profile k=4 m=2 d=5 plugin=jerasure technique=cl_msr ruleset-failure-domain=osd