ERAID: a New Storage Architecture for Mid/Large RAID

Referring to the concept of “distributed virtual disks” in cluster file system, this paper proposes a new storage architecture for mid/large-scale RAID – ERAID, which consists of several different structure SubRAIDs. Clients data can migrate into optimal SubRAID dynamically according to their access characteristics; the number of SubRAID and the structure of each SubRAID can also be adjusted to the evolution of system load, thus the whole ERAID system can always provide a virtual disk for each client to satisfy its I/O need. Simulation results demonstrate significant I/O performance advantage in ERAID, compared with the traditional mid/large-scale RAID5 or RAID1 of the same storage space.