RAID LEVELS
RAID LEVEL 4: | JetStor RAID 4 Storage Systems
Each entire block is written onto a data disk. Parity for same rank blocks is generated on Writes, recorded on the parity disk and checked on Reads.
RAID Level 4 storage systems require a minimum of 3 drives to implement.
Characteristics & Advantages
- Very high Read data transaction rate
- Low ratio of ECC (Parity) disks to data disks means high efficiency
- High aggregate Read transfer rate
Disadvantages
- Quite complex controller design
- Worst Write transaction rate and Write aggregate transfer rate
- Difficult and inefficient data rebuild in the event of disk failure
- Block Read transfer rate equal to that of a single disk
