Differences between RAID 0 and RAID 1
Contents
RAID 0 vs. RAID 1
RAID 0 and RAID 1 are two of the most basic configurations of RAID (Redundant Array of Independent Disks), a storage technology that combines multiple disk drives into a single logical unit.[1][2] While both aim to improve how data is stored, they do so with different goals. RAID 0 focuses on increasing performance, whereas RAID 1 prioritizes data redundancy.[3][4] The choice between them depends on whether speed or data protection is more critical for the intended application.[5]
RAID 0, also known as striping, splits data into blocks and writes them across two or more drives. This parallel operation significantly increases read and write speeds.[5][4] However, RAID 0 provides no fault tolerance; if one drive fails, all data in the array is lost because there is no redundancy.[5]
In contrast, RAID 1, or mirroring, writes an identical copy of data to two or more disks simultaneously. This configuration offers high fault tolerance, as the system can continue to operate using the mirrored copy if one drive fails. The primary trade-off is a reduction in storage efficiency, as the total usable capacity is limited to the size of a single drive.[3]
Comparison Table
| Category | RAID 0 | RAID 1 |
|---|---|---|
| Primary Goal | Performance[4] | Redundancy[3] |
| Technique | Striping (data is split across drives) | Mirroring (data is duplicated on drives) |
| Minimum Drives | 2 | 2 |
| Fault Tolerance | None; a single drive failure results in total data loss. | High; the array can withstand the failure of all but one drive. |
| Storage Capacity | Full capacity of all disks combined | Capacity of a single disk (50% efficiency for a two-disk array) |
| Read Performance | High; data is read from multiple disks at once. | High; data can be read from any disk in the mirror. |
| Write Performance | High; data is written to multiple disks simultaneously. | Slower than a single drive, as data must be written to all disks in the array. |
| Common Use Cases | Video editing, gaming, and temporary data storage where speed is critical. | Storing operating systems, databases, and critical files where data protection is essential. |
RAID 0 (Striping)
RAID 0 works by dividing data into smaller segments and striping them across multiple disks.[1] By accessing all drives in the array simultaneously, the system can achieve significantly higher data transfer rates than a single drive.[5] This makes RAID 0 a suitable choice for applications that require high-speed access to large files, such as video editing and high-performance computing.[3] The total storage capacity of a RAID 0 array is the sum of the capacities of all the drives in the set.
The main drawback of RAID 0 is its complete lack of redundancy. Because data is split across all the disks, the failure of any single drive will cause the entire array to become inaccessible, leading to the loss of all data.[5] Therefore, it is best used for non-critical data or in situations where data is backed up elsewhere.
RAID 1 (Mirroring)
RAID 1 provides data redundancy by writing the exact same data to two or more disks, creating a "mirror" of the information.[1] The primary benefit of this method is high fault tolerance. If one disk in the array fails, the system can seamlessly switch to the other disk(s), ensuring continuous operation without any data loss. This makes RAID 1 a reliable choice for storing critical data, such as operating systems or important documents.
While read performance in a RAID 1 array can be good because data can be read from any of the drives, write performance is generally slower than that of a single drive because the data must be written to all disks in the array. The most significant disadvantage of RAID 1 is its storage inefficiency. Because all data is duplicated, only 50% of the total disk capacity is usable in a standard two-drive setup.
References
- ↑ 1.0 1.1 1.2 "liquidweb.com". Retrieved December 30, 2025.
- ↑ "westerndigital.com". Retrieved December 30, 2025.
- ↑ 3.0 3.1 3.2 3.3 "stationx.net". Retrieved December 30, 2025.
- ↑ 4.0 4.1 4.2 "diskinternals.com". Retrieved December 30, 2025.
- ↑ 5.0 5.1 5.2 5.3 5.4 "techtarget.com". Retrieved December 30, 2025.
