Definition
RAID 5EE is a variation of the RAID 5E configuration that incorporates RAID 5E features but with better spare drive features. It organizes multiple hard drives in a computer to improve performance and data protection.
Moreover, RAID 5EE allocates spare capacity across all drives, allowing the system to use it instantly when needed. While this configuration can improve and protect your computer’s performance, you might not need it. It is common in large setups where speed and data security are essential.
RAID 5 vs. RAID 5EE
Choosing between RAID 5 and RAID 5EE depends on specific requirements such as system performance, rebuild speed, and hardware or controller. Here is the difference.
Data Handling
- In RAID 5, data is stripped across multiple drives, and parity ensures fault tolerance. Parity data is distributed evenly among all disks.
- Data striping and parity are similar in RAID 5EE, but it also integrates a distributed hot spare into the array.
Fault Tolerance
- RAID 5 can use parity data for reconstruction to recover information from a single drive failure.
- RAID 5EE uses integrated distributed hot spare and parity data to tolerate a single drive failure.
Performance
- While RAID 5’s read operations are efficient, its write operations, which involve calculating and recording parity data, are slower.
- The distributed nature of the spare space helps the RAID 5EE recover data quickly. As a result, RAID 5EE has better build performance than RAID 5.
Capacity
- In RAID 5, the capacity of one drive is reserved for parity. For example, in a configuration with three drives, the usable space is the capacity of two drives.
- Although RAID 5EE has parity overhead like RAID 5, it enhances capacity utilization by allocating the hot spare space across the entire array.
Rebuild Process
- If a drive fails, RAID 5 recreates data from the remaining drives using parity data. This process may be lengthy, especially in large arrays.
- The distributed hot spare allows RAID 5EE to rebuild faster. In case of a failure, the system starts rebuilding immediately without waiting for a separate spare drive to come online.