Block storage provides low-level access to disk capacity. Unlike file-based systems, data is not organized into a folder hierarchy but is split into fixed-size chunks called blocks. Each block is assigned a unique identifier or Logical Block Address (LBA), allowing the operating system or application to read and write data directly without file system overhead.
How it works and Use Cases
When attached to a server, a block device appears as a raw disk. The administrator can initialize it, create partitions, and format it with any file system like ext4, NTFS, or ZFS. Communication typically occurs over iSCSI, Fibre Channel, or NVMe-oF protocols, ensuring high throughput and low latency for data-intensive operations.
- Hosting relational databases (PostgreSQL, Oracle, SQL Server) that require precise control over data placement.
- Creating boot volumes for virtual machines in cloud environments.
- Running transactional workloads and high-performance computing (HPC) tasks.
Fact: Block storage performance is measured in IOPS (Input/Output Operations Per Second) and throughput. In modern cloud infrastructures, leveraging NVMe-based block volumes can provide over 64,000 IOPS per volume with sub-millisecond latency.