Storage performance tier (Standard vs Premium)
What it is
Together with kind, the performance tier chooses the backing hardware. Standard = magnetic/HDD-class (cost-effective, GB on-the-fly) and Premium = SSD-backed (high IOPS + throughput, low latency, priced higher). Standard is also called general-purpose; premium comes in account kinds like Premium block blobs and Premium file shares.
Why it exists
Not all workloads need SSD. Tiered per account = the sweet spot between cost and IO performance so you don’t overpay for a backup archive on premium SSD, nor starve a transactional database on HDD.
Key ideas
- Standard general-purpose v2 — the common default; supports blobs, files, tables, queues; auto access tiers.
- Premium block blob storage (PA_BLOB) — high performance for high-throughput block blobs (e.g., analytics, IoT); no access tiers.
- Premium file shares — SMB/NFS on SSD; for database/file workloads needing consistent low latency. Backed by premium SSD-managed data.
- Premium page blobs — foundation for unmanaged VM disks and premium SSD-powered managed disks (also used by VMs).
- Premium accounts generally have higher per-GB cost but better IOPS/latency; Standard is elastic.
How it fits (diagram)
Exam notes
- Performance = hardware (SSD vs magnetic); Kind = which services & features. Pick both at creation.
- Premium block blobs have no access tiers (hot-only).
- Premium file shares enable low-latency consistent IOPS for file workloads.
- VM disks: page blobs = unmanaged attached disks; premium = SSD-backed.
Related
storage-account · blob-storage · azure-files · redundancy-lrs-zrs-grs
📘 Source: Microsoft Learn — Storage Performance