Suboptimal Service Tier Selection in Azure SQL Managed Instance

Next-gen General Purpose is an upgrade of the General Purpose tier, while moving from Business Critical to it is a tier downgrade with latency and read-scale trade-offs; zone redundancy for Next-gen General Purpose is currently in preview. The newer tier enables more granular scaling of vCPU, memory, and storage, allowing workloads to better match actual resource needs. In many cases, workloads running on Business Critical - or overprovisioned legacy General Purpose-do not require the premium performance or architecture of those tiers and could achieve equivalent outcomes at lower cost by moving to next-gen General Purpose.

Azure SQL Managed Instance is billed based on service tier, vCPU, memory, and storage configuration. The next-gen General Purpose tier offers improved performance characteristics and independent scaling of compute and storage at the same baseline cost as General Purpose (including 3 free IOPS per GB of reserved storage), though IOPS above that and memory above the default memory-to-vCore ratio are billed separately, while Business Critical incurs higher infrastructure and licensing costs.

• Review which SQL Managed Instances are running on the original General Purpose architecture or on Business Critical
• Assess whether workloads truly require Business Critical capabilities (e.g., low-latency IO, high concurrency)
• Identify instances where compute, memory, or storage appear overprovisioned relative to workload needs
• Evaluate whether current tier selection reflects historical constraints rather than current platform options

• Migrate eligible SQL Managed Instances to the next-gen General Purpose tier
• Rebalance vCPU, memory, and storage independently to align with actual workload requirements
• Periodically reassess tier selection as platform capabilities and pricing evolve

https://learn.microsoft.com/en-us/azure/azure-sql/managed-instance/service-tiers-next-gen-general-purpose-use