documentdb-storage

name	documentdb-storage
description	Storage configuration guidance for Azure DocumentDB — when and how to use Premium SSD v2 high-performance storage, IOPS/bandwidth caps that are gated by compute tier (not disk size), Premium SSD v2 limitations (no CMK, migration paths, disk-hydration sequencing), and storage capacity change limits. Use when picking a storage type at cluster creation, sizing for I/O-intensive workloads, migrating from Premium SSD to Premium SSD v2, or sequencing compute/storage/HA changes on a Premium SSD v2 cluster.
license	MIT

Storage — Azure DocumentDB

Azure DocumentDB clusters use remote premium SSD storage. Two disk types are offered:

Storage type	IOPS / bandwidth scaling	Max IOPS	CMK	Use it for
Premium SSD (v1)	Scales with disk capacity — bigger disk → higher IOPS	20,000	✔️	Legacy clusters, scenarios that require CMK
Premium SSD v2	Decoupled from disk size — IOPS/bandwidth gated by compute tier	80,000	❌	New production clusters; any I/O-intensive workload

Premium SSD v2 is the default recommendation for new clusters. It delivers up to a 12× performance boost at no added cost by removing the disk-size lever from the IOPS equation — you size storage for capacity and size compute for throughput, independently.

How Premium SSD v2 changes sizing