Some Raid Issues
Granularity
- fine-grained: stripe each file over all disks. This gives high thruput for the file, but limits to transfer of 1 file at a time
- course-grained: stripe each file over only a few disks. This limits thruput for 1 file but allows more parallel file access
Redundancy
- uniformly distribute redundancy info on disks: avoids load-balancing problems
- concentrate redundancy info on a small number of disks: partition the set into data disks and redundant disks