Primitive
Block Storage
Raw, low-latency block devices that attach to a single compute instance like a physical disk.
Description
Block storage (AWS EBS, GCP Persistent Disk, Azure Disk) attaches a raw, low-latency volume to a compute instance, with snapshots and online resizing across all three. They differ in the available volume types (SSD vs HDD, provisioned-IOPS vs general-purpose), the per-volume IOPS and throughput ceilings, and whether and how a volume can be attached to more than one instance. On-prem block storage from hardware vendors offers the same role with self-managed arrays. To the best of our knowledge the primitive is equivalent; choose based on the IOPS/throughput tier and durability your workload needs.
Capabilities
- Attach as a disk to one instance
- Low-latency random read/write
- Snapshots and resizing
- Back any filesystem or database