Azure SQL performance tuning

Performance tuning of SQL Workloads in Azure: best practices for 2025

SQL Performance Tuning in Azure: Best Practices for 2025. Optimize your SQL workloads in Azure with modern tuning techniques. Learn how to improve performance through automation, intelligent insights and resource governance.


Introduction

In a cloud environment, one golden rule applies: performance = cost. A poorly optimized SQL workload in Azure can not only slow down your application, but also blow your cloud budget. Fortunately, Azure offers a range of powerful tools and techniques for tuning SQL performance – from automatic recommendations to advanced workload analytics.

In this blog, we dive into the best practices for 2025 and show you how to future-proof SQL performance in Azure.


Why performance tuning is critical in Azure

  • Cloud is pay-per-use: bad queries = higher compute costs

  • Scalability has limits without optimization

  • Customer satisfaction depends on response times

  • Governance and SLAs require predictable performance


Essential performance tools in Azure SQL

🔹 1. Intelligent Performance Features (PaaS).

  • Automatic Tuning: auto-indexing and query plan correction

  • Intelligent Insights: detects performance degradation and makes recommendations

  • Query Store: stores query statistics for analysis and regression control

🔹 2. Azure Monitor & Log Analytics

  • Real-time visibility into CPU, IOPS, DTU/vCore consumption

  • Link with Application Insights for end-to-end tracing

  • Configure alerts based on latency, deadlocks or throttling

🔹 3. Index Strategy & Query Optimization

  • Analyze missing indexes, unused indexes and over-indexing

  • Use execution plans & sys.dm_exec_query_stats

  • Optimize joins, filters, parameters and batch processing

🔹 4. Resource governance

  • Understand the difference between DTU model and vCore model

  • Reserve sufficient IOPS with Azure SQL VMs (Premium SSDs)

  • Use Elastic Pools for workloads with varying loads


Performance tuning tips by SQL variant

SQL Workload Type Approach & Tools
Azure SQL Database Automatic Tuning, Serverless Configuration
SQL Managed Instance Intelligent Insights + Elastic Pooling
SQL Server on Azure VM Traditional tuning + Azure Monitor & storage tuning

Best practices for 2025

  1. Automate where possible, but always monitor.
    Let Azure help you, but keep manual oversight through Query Store and Insights.

  2. Conduct periodic workload reviews.
    Consider performance testing after release cycles or data growth.

  3. Implement CI/CD with performance regression testing.
    For example, with Data-Tier Applications (DACPAC) + query performance benchmarks.

  4. Make tuning part of governance.
    Link KPIs to database latency and throughput.


❌ Common mistakes

  • Not using auto-tuning features

  • No view of redundant indexes

  • Scaling up blindly without root cause analysis

  • Lack of query lifecycle management


🎯 Call to Action

📊 Want to really optimize your SQL performance in Azure? Get advice from our Azure experts or schedule a quick scan directly atinfo@improfs.nl. Or you can comment below!