It is becoming increasingly important for organizations to optimize MySQL performance. This is especially true as more organizations opt to deploy MySQL instances in cloud and hybrid environments. While cloud and hybrid hosting has many advantages, organizations should be aware that the added complexity introduces more opportunity for deficiencies.
MySQL database administrators (DBAs) are responsible for MySQL optimization – making sure their databases are available and performing up to user expectations. Failure on either of these counts will usually result in a call from disgruntled users or supervisory figures.
Most DBAs prefer to avoid that type of extracurricular contact and would prefer their databases to always exhibit sterling performance.
Why Do You Need to Optimize MySQL Performance?
Unfortunately, database performance issues are not about to suddenly disappear. Even finely tuned databases may become problematic over time. As developers add new queries, the volume of data grows, and the number of concurrent users increases. What was once a smoothly running system may become bogged down with performance issues.
Many factors affect MySQL performance. A simplified description of how relational databases like MySQL are used is that SQL queries are executed against stored tables of data to provide results. Queries can be very simple or extremely complex and take widely varying amounts of time to finish execution and return results.
In some cases, long-running queries may not lend themselves to optimization. But in many instances, there are measures DBAs can take to improve the speed with which SQL queries execute.
Such measures include:
The inefficient use of indexes is the culprit behind many MySQL performance issues. It’s not a simple problem to solve, as both over and under-indexing can negatively impact the speed with which queries execute. Through the use of profiling, DBAs can identify missing indexes or those that are not being used.
Indexing the correct columns in a table is critical. Incorrect indexing can increase query cost and execution time. DBAs need to create missing indexes where appropriate, drop unused indexes that impact execution and reevaluate the indexing structure to successfully optimize queries.
Table order in JOINS
Another issue that can cause substantial impacts to SQL queries is the order in which tables are called in JOIN statements. The order is irrelevant for INNER JOINS. No appreciable changes in performance will be achieved by modifying these statements.
That is not the case with OUTER or LEFT JOINS. In these statements, the execution speed is based on the number of rows involved in the operation. Modifying the order of your tables in OUTER JOINS can have a big impact on database performance.
There are other reasons databases may be sluggish, but these two are excellent places to start. Tuning indexes and JOINS can significantly improve the performance of MySQL systems.
Identifying Performance Roadblocks
The first step in addressing a performance issue is identifying its cause. One of the big changes brought about by hosting databases in the cloud is the inability to just throw hardware at potential problems in the hope of a simple resolution. Your cloud provider has likely furnished the appropriate hardware for the MySQL database experiencing performance issues.
The poor performance of MySQL databases is often a result of the way the system’s SQL queries are constructed. Addressing the issues discussed in the previous section of this article is the way to speed up your databases and optimize MySQL performance. The difficulty lies in isolating the queries that are negatively impacting performance.
Teams need a monitoring platform that can pinpoint the problem queries so they can be optimized. The tool needs to be able to identify long-running and blocked queries. It should also report on the queries taking the most execution time to complete. With this knowledge, DBAs can begin to work on optimizing MySQL instances, prioritizing the queries with the greatest impact on overall database performance.
The Right Tools for the Job
In the age of hybrid environments, a company may be hosting MySQL databases in multiple locations. The ability to monitor these locations from a single tool is preferred by support teams over the complications of learning and using different solutions. Centralized monitoring of the complete MySQL environment that encompasses on-premises and cloud databases gives DBAs a complete picture and increases overall team productivity.
SQL Diagnostic Manager for MySQL is a comprehensive MySQL and MariaDB performance monitoring tool for MySQL optimization. It can help identify problem queries as candidates for optimization.
It enables DBAs to find the top 10 queries based on execution time and provides real-time monitoring to enable fast corrective actions to be taken by support teams. It’s an agentless monitoring solution that also monitors database space, security, and user access issues.
SQL Diagnostic Manager for MySQL is a versatile tool that monitors on-premises database instances as well as cloud instances on Amazon RDS, Azure Database, Google Cloud SQL, and Oracle Cloud Service. It enables teams to create customized dashboards to meet requirements for specific environments.
We invite MySQL DBAs and support teams to view an IDERA webcast hosted by Pinal Dave that talks about the specific tuning tactics and strategies mentioned above to improve MySQL database performance. The webcast concludes with a demonstration of SQL Diagnostic Manager for MySQL in action by Ray Rios.
SQLyog is the software tool used throughout the demonstration to run SQL queries and obtain statistics related to their execution. It provides many features to streamline MySQL DBA and developer tasks that are critical when optimizing SQL queries. The functionality of SQLyog complements the diagnostic information provided by SQL Diagnostic Manager for MySQL.
In combination, they give a database team a powerful set of tools with which to optimize MySQL performance wherever systems are hosted.