Azure SQL Database Hyperscale - Named Replicas feature is Generally Available (GA)

GermanD80: There could be multiple factors for the same and it could be environment specific as well. I would suggest raising an incident with Microsoft support team to perform through investigation. I am sharing few of the scenarios below:

- Data Latency

Named replicas rely on the transaction log service to keep data in sync with the primary replica. If the primary database is under heavy load, the rate at which transaction logs are generated and forwarded to the named replicas can increase, leading to higher data latency. This means that the named replica might not have the most recent data, causing delays in query execution. 

You can use Azure Monitor/DMVs to track data latency between the primary and named replicas. This can help identify if high latency is contributing to the slow query performance.

- Resource Contention

Heavy load on the primary database can lead to resource contention, affecting the performance of the transaction log service and other background processes that are responsible for syncing data with named replicas. 

- Compute and Storage Configuration

The performance of named replicas can also be influenced by their compute size. If the named replicas are not provisioned with sufficient resources (e.g., vCores/service level objective (SLO)), they may struggle to handle the query load, especially when the primary database is under stress. Please ensure that the named replicas are provisioned with adequate compute resources to handle the query load. Adjust the service level objective (SLO) if necessary to provide more resources.