RAID (Redundant Array of Independent Disks) is like having backup copies of your important files stored in different places on several hard drives or solid-state drives (SSDs). If one drive stops working, your data is still safe because you have other copies stored on the other drives. It’s like having a safety net to protect your files from being lost if one of your drives breaks down.
RAID (Redundant Array of Independent Disks) in a Database Management System (DBMS) is a technology that combines multiple physical disk drives into a single logical unit for data storage. The main purpose of RAID is to improve data reliability, availability, and performance. There are different levels of RAID, each offering a balance of these benefits.
Key Evaluation Points for a RAID System
Reliability: How many disk faults can the system tolerate?
Availability: What fraction of the total session time is a system in uptime mode, i.e. how available is the system for actual use?
Performance: How good is the response time? How high is the throughput (rate of processing work)? Note that performance contains a lot of parameters, not just the two.
Capacity: Given a set of N disks each with B blocks, how much useful capacity is available to the user
