SQL Server Performance Tuning – 9 Ways to Keep Your Database Running Smoothly

SQL Server Performance Tuning – 9 Ways to Keep Your Database Running Smoothly

SQL Server performance tuning could be a powerful and feature-rich management platform that may support a good range of applications, but nobody will care how good the platform is if queries aren’t performing well or workloads are experiencing deadlocks, latency issues, and other service disruptions. The performance of the appliance is their only concern. This text outlines nine SQL Server performance tuning best practices.

Implementing a sturdy performance tuning strategy that considers all aspects of the SQL Server environment is the best thanks to making sure that SQL Server can meet its performance requirements. This includes not only indexes and queries, which are frequently the main focus of tuning efforts, but also the hardware infrastructure, server and database settings, log and data files, and the other environment-supporting components.

In this article, I’ll show you the way to perform performance tuning in an exceedingly SQL Server environment using nine best practices. Each best practice may be a broad enough topic in and of itself to warrant its own article (or series of articles or maybe a book or two). As a result, these best practices—or guidelines—should only be used as a place to begin, with the understanding that you simply should research each topic further to realize an improved understanding of what is involved. The rules are only intended to induce you to start on your thanks to effective performance tuning and supply you with a foundation.

1. Determine the hardware you’ll have supported your performance requirements

The hardware infrastructure that supports your SQL Server environment is usually answerable for performance issues. The higher your infrastructure is planned, the less likely you’re to experience hardware-related performance issues with any of the subsequent resources:

• Compute: SQL Server may be a resource-intensive application that necessitates sufficient processing and memory to manage data and drive workloads, whether transactional, analytical, business intelligence, bulk loads, or a changing mix. Applications settle down responsive and should even finish off if processors or memory can’t continue.
• Storage: SQL Server requires storage solutions that will handle the expected volumes of information while also supporting the varied data access methods. Organizations can select from a spread of storage options in today’s market, but only some are suitable for SQL Server. Whatever storage solution organizations choose, they must be able to deliver the desired input/output operations per second (IOPS) while minimizing latency.
• Network: If the network can’t maintain workload demands, performance issues can arise. Although SQL Server is also running smoothly and queries are also optimized for speed, network bottlenecks can cause long response times, slowing down applications and even causing time-outs.

When you’re planning a SQL Server implementation, ensure your infrastructure can support all of your workloads. If you’ve already installed SQL Server and are experiencing performance issues, you ought to assess your current hardware to determine if it is the source of your issues.

2. When configuring your SQL Server instance, keep performance in mind

You should consider performance from the start, even as you ought to with hardware, which includes when you’re first fitting your SQL Server instances. You will want to deploy instances for various environments, like development and production, or install SQL Server on a machine dedicated to its instance.

SQL Server also has configurable settings that you simply can change to satisfy your workload’s specific needs. The server memory options, for instance, allow you to line the minimum and maximum amounts of server memory, in addition to index creation memory and minimum query memory. For instance, if you have got several SQL Server instances running on a server or cluster and do not want them to compete with each other, you’ll lower the memory for every instance. Other options, like those associated with parallelism and deadlock priority, also are available in SQL Server.

When changing configurations, you need to use caution. As an example, you may specify an oversized number of maximum worker threads in the hopes of improving performance, only to find that it’s delayed an application. Alternatively, you’ll implement backup compression only to find that it’s consuming valuable CPU resources and interfering with concurrent operations. Setting trace flags should even be through with caution. Although they will be useful for troubleshooting performance, they will also cause disruptions, which is why any changes you create should be thoroughly tested before going into production.

3. When configuring your databases, keep performance in mind

At the database level, SQL Server offers a variety of options for improving performance. You’ll be able to put your log and data files on different physical drives, for instance, to avoid file contention while accommodating different access patterns. Looking at your workloads, you will also find it useful to regulate the Auto growth and Max size file settings for these files.

You can configure settings at the database level in SQL Server, even as you’ll at the server level. You can, for instance, founded asynchronous statistics updates and enable or disable the Auto Create Statistics and Auto Update Statistics options. You’ll also change the database compatibility level, which is helpful if you’ve recently upgraded SQL Server.

You’re not limited to using databases and their properties when addressing database performance issues. You may even be able to improve performance by optimizing the tempdb system database, which may have an unexpected impact on performance by causing metadata or object allocation contention. A way to boost the database’s performance is to stay its files become independent from the user databases and therefore the software package. Adjusting the amount of tempdb data files or their sizes is an alternative choice.

4. Create databases that are optimized for performance

A good database design isn’t only important for data integrity, but it may also help with performance. A normalized database, for instance, can improve performance by reducing redundant data, making write and, in some cases, reading operations easier, especially if just one table is involved. However, if used wisely, a touch renormalization may benefit your queries in some cases.

Choose the foremost appropriate data types for your data when designing a database, like char rather than varchar for string values that are all two characters. You ought to also give some thought to what reasonably data you will be stored in SQL Server. It’s often preferable to store the image path instead of the image itself in a very database. Foreign keys and other constraints, when used correctly, can improve performance.

You should consider how other database objects can affect performance additionally to tables. For instance, you’ll frequently avoid complex queries by encapsulating them in views and indexing the views (keeping in mind best indexing practices). Another example could be a stored procedure, which may often outperform a question in terms of performance. When creating stored procedures, however, ensure to follow best practices, like including the SET NOCOUNT ON clause and avoiding the sp_ prefix when naming the procedures.

5. Create indexes to assist, not hinder, performance

Some companies, particularly those without experienced DBAs, are tempted to stay adding indexes to their tables in the hopes of improving performance; only to seek out that performance has steadily deteriorated. Proper indexing necessitates a much more nuanced approach, one that considers both the info and therefore the sorts of queries being run.

The rules for correct indexing are numerous and much too numerous to list here, but here are some things to stay in mind:

• Indexes should be created to support the columns that are being queried, particularly in joins and query predicates.
• Column order should be supported by how the columns are queried when creating an index with multiple columns.
• If you cannot clearly demonstrate the advantages of indexes on small tables, don’t use them.
• Do not index a column with a tiny low number of unique values.
• Check indexes for fragmentation on an everyday basis, then rebuild or reorganize them as required.
• To avoid unnecessary overhead, identify and take away unused or underutilized indexes.
• Sort indexes consistent with how the information is queried.
• Check to work out if your queries are using the indexes as they ought to.
• When possible, use covering or filtered indexes, keeping in mind the categories of queries you will be supporting.

These are just some of the factors to think about when creating indexes for your tables and views. Indexing correctly must be approached with caution, or it can seriously impede performance instead of aid it.

6. Create queries to induce the foremost out of your system

Optimizing your T-SQL queries is one of the foremost important steps you’ll go for improving SQL Server performance, and it is a task so complex and nuanced that entire books are written on the topic. Several factors must be considered by the diligent database developer, including the following:

• Avoid using SELECT * in your queries and only retrieve the fields you need.
• When calling a database object, include the schema name.
• Unless you wish to grasp the number of rows stricken by a question, use the SET NOCOUNT ON clause in your queries.
• Avoid implicit conversions, which force the query engine to convert data that may not be needed.
• If the least possible, keep the number of queries per session to a minimum and transactions to a minimum.
• Recognize the differences between temporary tables, table variables, and customary table expressions, and when to use each.
• Instead of correlated sub queries, use joins.

These are just some of the various considerations to create when optimizing your T-SQL queries. Additionally, before going into production, your scripts should undergo a radical code review and be thoroughly tested. Developers should also make small changes to their queries instead of making large changes all directly so they will see what worked and what didn’t.

7. Maintain an up-to-date SQL Server environment

Although it’s going to appear that this best practice is self-evident, the importance of keeping hardware, software, and firmware up to now cannot be overstated. To require advantage of the latest performance-related features, you ought to consider updating to a newer version of SQL Server whenever possible. Microsoft, as an example, introduced memory-optimized tempdb metadata in SQL Server 2019, which may help workloads that rely heavily on the tempdb database perform better.

Even if you choose to not upgrade to a more modern SQL Server version, you ought to update your SQL Server instances and also the underlying Windows OS on an everyday basis to require advantage of any recent performance improvements. Furthermore, you ought to consider updating any hardware that’s causing performance issues. Whether or not the hardware isn’t replaced, the supporting software and firmware should be preserved so far.

8. Make use of SQL Server tools to spice up performance.

SQL Server includes a variety of performance-enhancing features. When it is smart, anyone trying to optimize a SQL Server environment should use these tools, especially since they’re included within the licensing fees. The subsequent are a number of the SQL Server tools:

• The Microsoft Database Engine Tuning Advisor (DTA) analyses your databases and makes recommendations for query performance optimization. The tool is often accustomed to troubleshooting a question, tuning a collection of queries across multiple databases, managing space for storing, and performing what-if analysis of design changes.
• SQL Server Query Store allows you to avoid wasting a history of queries, execution plans, and runtime statistics for later analysis of database usage patterns and query plan changes. Query Store can assist you in detecting and correcting query performance regressions caused by plan changes, moreover as identifying and tuning resource-intensive queries.
• SQL Server Extended Events may be a lightweight performance monitoring system that permits you to gather the info you wish to diagnose and resolve performance issues. You’ll be able to specify which events to trace and the way to store event data when creating an extended events session. You’ll gather precisely the information you would like about your SQL Server environment in this manner, and so view it within the format that most closely fits your needs.
• There are several options in SQL Server Management Studio (SSMS) for viewing details of a few query executions. You’ll view a query’s actual execution plan, which incorporates runtime information like resource usage metrics and warnings, or use the Live Query Statistics feature to determine real-time data about the query execution process. Client statistics about queries and their related network packets are available in SSMS.
• Many dynamic management views (DMVs) are available in SQL Server, and plenty of them can assist in identifying performance issues. The sys. dm os wait stats DMV, for instance, are often wont to see the waits experienced by executed threads, which may facilitate your diagnosis performance issues with SQL Server and specific queries. DMVs in SQL Server are server-scoped or database-scoped.

The more you understand the way to use SQL Server’s tools, the more effectively you’ll be able to identify and resolve performance issues. However, older SQL Server or SSMS editions might not have access to certain tools or features. Furthermore, the tools listed here don’t seem to be the sole ones that are available. As an example, Microsoft’s Database Experiment Assistant (DEA), an A/B testing solution for SQL Server upgrades, is out there for download.

It’s definitely worth looking into what other tools and features may be available to assist you with performance issues. Even the error logs may be helpful in detecting potential performance issues.

9. Monitor, Monitor, Monitor

Consistent performance across all SQL Server databases and instances necessitates ongoing monitoring. But simply collecting telemetry from your systems isn’t enough. You want to even be able to diagnose and resolve performance issues using the information you’ve gathered. A monitoring solution can provide you with a warning of potential issues, assist you in identifying bottlenecks, and reveal trends that will indicate performance issues over time.

There aren’t any hard-and-fast rules about what you ought to monitor, and you must certainly tailor your monitoring strategy to your unique circumstances. However, there are some areas that you simply should pay special attention to. You will likely want to stay a watch on index fill factors, fragmentation, and usage, for instance. Monitoring metrics like CPU, memory, I/O, and buffer cache usage, similarly to metrics associated with log and data files, is also beneficial. You must keep track of metrics specific to your queries moreover.

You’ll need a monitoring solution that will track the metrics you would like without affecting application performance or database operations to properly monitor your SQL Server environment. The answer should be ready to track all relevant metrics, transmit timely notifications, and provides you the knowledge you would like to quickly diagnose and resolve performance issues. You’ll use Microsoft’s System Monitor (also called Performance Monitor), which is free, but many administrators prefer an answer like Enteros’s SQL Monitor, which has more robust features.

Performance Tuning May be a Continuous Process

Performance tuning isn’t something you are doing once so dump until everything goes wrong. It is a long-term project that necessitates constant attention to any or all aspects of the SQL Server environment. The infrastructure that houses the environment, the queries that access the info, the indexes that support the queries, the server and database settings that affect performance, and everything in between are all included in performance tuning.

However, you must proceed with caution when tuning the environment, making changes in small steps and thoroughly testing them before putting them into production. Above all, performance tuning shouldn’t be treated as an afterthought; rather, it should be considered an integral part of your management and optimization efforts, beginning with the initial setup of your SQL Server environment and continuing until the environment is decommissioned.

About Enteros

Enteros offers a patented database performance management SaaS platform. It proactively identifies root causes of complex business-impacting database scalability and performance issues across a growing number of RDBMS, NoSQL, and machine learning database platforms.