# disk array

> disk storage system which contains multiple disk drives

**Wikidata**: [Q1228738](https://www.wikidata.org/wiki/Q1228738)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Disk_array)  
**Source**: https://4ort.xyz/entity/disk-array

## Summary
A disk array is a disk storage system that contains multiple disk drives, designed to provide increased data reliability, availability, and performance compared to single-disk solutions. It is a fundamental component of modern computer storage infrastructure, enabling efficient data management and protection.

## Key Facts
- A disk array is classified as computer storage media and computer hardware.
- It is a subclass of cluster, massive array of idle disks, and hybrid array.
- The term "disk array" has aliases including RAID array, drive array, storage disk array, and storage array.
- It uses RAID disk technology for data redundancy and performance.
- Disk arrays have parts including disk array controllers, cache (both non-volatile and random-access memory), and hard disks.
- They are used by network-attached storage, storage area networks, and storage virtualization systems.
- The Wikipedia page for disk array is available in 8 languages: Arabic, German, English, French, Japanese, Polish, Russian, and Ukrainian.
- The entity has a sitelink count of 8, indicating its presence across multiple language editions.

## FAQs
### Q: What is the primary purpose of a disk array?
A: A disk array is designed to store data across multiple disk drives simultaneously, providing improved performance, capacity, and reliability compared to single-disk storage systems.

### Q: How does a disk array differ from a single hard drive?
A: Unlike a single hard drive, a disk array distributes data across multiple disks using technologies like RAID, offering redundancy, faster data access, and protection against disk failure.

### Q: What are the main components of a disk array?
A: A disk array consists of multiple hard disk drives, a disk array controller, and often includes cache memory (both non-volatile and random-access) for improved performance.

## Why It Matters
Disk arrays represent a critical evolution in data storage technology, addressing the fundamental limitations of single-disk systems. By distributing data across multiple drives, they solve the critical problems of data availability and performance that plague individual storage devices. When one disk fails in a properly configured array, the system continues to operate without data loss, providing business continuity and protecting against catastrophic data loss. This redundancy is essential for enterprise environments where downtime costs can reach thousands of dollars per minute. Additionally, disk arrays enable parallel data access across multiple drives, dramatically improving read and write speeds compared to single-disk solutions. This performance enhancement is crucial for applications requiring high throughput, such as databases, virtualization platforms, and media streaming services. The technology has become foundational to modern computing infrastructure, from personal NAS devices to massive data center storage systems, enabling the data-intensive applications that power today's digital economy.

## Notable For
- Being the foundation of RAID (Redundant Array of Independent Disks) technology, which revolutionized data storage reliability
- Enabling the development of storage area networks (SANs) and network-attached storage (NAS) systems
- Providing the scalability needed for enterprise-level data storage solutions
- Incorporating both hardware and software components for comprehensive data management
- Supporting various RAID levels that offer different balances of performance, capacity, and redundancy

## Body
### Technical Architecture
Disk arrays employ sophisticated controllers that manage data distribution across multiple physical drives. These controllers implement RAID algorithms that determine how data is striped, mirrored, or parity-protected across the array. The architecture typically includes both volatile and non-volatile cache memory to buffer read and write operations, significantly improving performance by reducing the latency of disk operations.

### RAID Implementations
Different RAID levels offer various trade-offs between performance, capacity, and data protection. RAID 0 provides pure striping for maximum performance without redundancy. RAID 1 offers mirroring for complete data redundancy. RAID 5 and RAID 6 implement parity-based protection, allowing arrays to survive single or double disk failures respectively while maintaining usable capacity. More advanced implementations like RAID 10 combine mirroring and striping for optimal performance and redundancy.

### Performance Characteristics
Disk arrays achieve superior performance through parallel access to multiple drives. When reading or writing data, operations can be distributed across all available disks simultaneously, multiplying the effective throughput. This parallelism, combined with intelligent caching strategies, enables disk arrays to handle workloads that would overwhelm individual drives. The performance benefits are particularly pronounced for sequential operations and applications with high I/O demands.

### Reliability Features
Beyond RAID protection, modern disk arrays incorporate numerous reliability features. Hot-swappable drive bays allow failed disks to be replaced without powering down the system. Predictive failure analysis monitors drive health and can alert administrators before catastrophic failures occur. Many arrays also support dual controllers for complete redundancy, ensuring continued operation even if the primary controller fails.

### Applications and Use Cases
Disk arrays serve diverse applications across the computing spectrum. In enterprise environments, they form the backbone of SAN and NAS infrastructure, providing shared storage for servers and virtualization platforms. Media and entertainment companies rely on high-performance arrays for video editing and rendering workflows. Scientific computing applications use arrays for large-scale data analysis and simulation. Even consumer-grade NAS devices employ array technology for home media storage and backup solutions.

## Schema Markup
```json
{
  "@context": "https://schema.org",
  "@type": "Thing",
  "name": "disk array",
  "description": "disk storage system which contains multiple disk drives",
  "url": "https://en.wikipedia.org/wiki/Disk_array",
  "sameAs": [
    "https://www.wikidata.org/wiki/Q15241312"
  ],
  "additionalType": "ComputerStorageMedium"
}

## References

1. Freebase Data Dumps. 2013
2. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)
3. Wikibase TDKIV