From RAID to Erasure Coding: A Deterministic Guide to Storage SLAs for AI and Analytics
The erasure coding vs RAID debate ends the moment a second drive fails mid-rebuild on a petabyte-scale cluster. I watched it happen firsthand in 2018 during a massive Hadoop cluster migration. We were pushing 20PB of data. A 14TB drive died. The controller started the rebuild, calculating parity bit by bit. Then, at 65% completion—statistical…