Author: Robert Agar

The working life of a DBA is often centered on optimizing their systems to provide users with the best performance. There are many aspects of a MySQL implementation that can be tuned to increase its functionality. These improvements will result in a more efficient system and enhanced user experience.

One of the problems facing the DBA responsible for instituting performance tuning is to identify the particular areas to address that will impact the system in a positive manner. Approaching this task in a haphazard fashion is not advisable. Randomly modifying parameters is just as likely to cause further issues than to lead to performance gains. Luckily, there is a solution to this dilemma.

Conducting focused monitoring can be instrumental in enabling the DBA to pinpoint the source of performance degradation. Armed with this knowledge, informed decisions can be made regarding how …

In week 3 of our series, Benefits of SQL Diagnostic Manager for MySQL (formerly Monyog), we discuss how to identify and analyze problematic SQL queries using SQL Diagnostic Manager for MySQL. If you missed it, feel free to read our previous post on Agentless Monitoring and Cloud Readiness.

Find Problematic SQL Queries

MySQL and MariaDB currently lack advanced tools for profiling SQL queries (such as SQL Profiler of Microsoft’ SQL Server). While other monitoring tools for MySQL and MariaDB provide monitoring and advisory information on various system metrics, they do not pinpoint the problematic SQL queries. No amount of hardware upgrades and tuning of the parameters in the database server configuration file ‘my.cnf’ and the database server initialization file …

In Percona Monitoring and Management (PMM) 1.13 we have adopted Prometheus 2, and with this comes a dramatic improvement in resource usage, along with performance improvements!

What does it mean for you? This means you can have a significantly larger number of servers and database instances monitored by the same PMM installation. Or you can reduce the instance size you use to monitor your environment and save some money.

Let’s look at some stats!

CPU Usage

We can see an approximate 5x and 8x reduction of CPU usage on these two PMM Servers. Depending on the workload, we see CPU usage reductions to range between 3x and 10x.

Disk Writes

There is also less disk write bandwidth required:

On this instance, the bandwidth reduction is “just” 1.5x times. …

MySQL 8 introduced a number of enhancements to improve both replication performance and the monitoring thereof. Improvements included more efficient replication of small updates on big JSON documents, the addition of Performance Schema tables for slave performance metrics, tracing and debug logging improvements, among others. With regards to monitoring, Group Replication has been improved by introducing new replication timestamps, additional columns to the performance schema, as well as by making the relationship between replication threads more efficient. We covered the various improvements to replication performance in the Replication Performance Enhancements in MySQL 8 blog. Today’s blog will provide some practical guidelines on monitoring your MySQL 8 master-slave and group (cluster) replication.

Two Types of MySQL Replication …

Please join Percona’s Principal Support Escalation Specialist Sveta Smirnova as she presents Troubleshooting Best Practices: Monitoring the Production Database Without Killing Performance on Wednesday, June 27th at 11:00 AM PDT (UTC-7) / 2:00 PM EDT (UTC-4).

Register Now

During the MySQL Troubleshooting webinar series, I covered many monitoring and logging tools such as:

• General, slow, audit, binary, error log files
• Performance Schema
• Information Schema
• System …

Since April 19th, when MySQL 8.0 became Generally Available (GA), the MySQL community has been abuzz with excitement over all of the new features and improvements. Many of new features were improvements to performance or monitoring, while others were specifically related to replication. We reviewed Replication Performance Enhancements in MySQL 8 recently. Today’s blog will describe how to set up a basic master-slave configuration with MySQL, using two servers on a single machine.

Replication Defined

MySQL replication is a process in which data from one MySQL database server (the master) is copied automatically to one or more MySQL database servers (the slaves). In the case of multiple slaves, these are usually referred to as a slave cluster. Replication should not to be confused with backup operations. Whereas the aim of backups is to protect the data and/or data structure, the role of replication is typically to spread …

The MySQL error log is an essential part of database server performance monitoring. Whenever something goes wrong or performance degrades, the Error Logs are usually the first place we look to start troubleshooting.

The MySQL Error Log is one of three related log types:

• The Error Log: It contains information about errors that occur while the server is running (as well as server start and stop events).
• The General Query Log: This is a general record of what mysqld is doing (connect, disconnect, queries).
• The Slow Query Log: It consists of “slow” SQL statements as defined in the long_query_time global variable.

You can enable error log monitoring to allow Monyog to keep an eye on your MySQL Error Log, and notify you when something goes awry. Moreover, Monyog combines the General Query, Slow Query and Error logs in a single view for both network and cloud servers. For example, in the …

MariaDB came into being the day that Oracle announced the purchase of Sun in 2010.  In order to keep it free under the GNU GPL, Michael Widenius forked MySQL and took several MySQL developers with him in the process.  Since then, MariaDB has been a drop-in replacement for MySQL, albeit with more features and better performance.

In the Improve MariaDB Performance using Query Profiling blog, we learned some useful techniques for tracking and analyzing slow queries using a couple of MariaDB server’s built-in tools: the Slow Query Log and the Performance Schema.  

The Slow Query Log records queries that are deemed to be slow and potentially problematic, that is, queries that take longer than the long_query_time global system variable value to run.

The Performance Schema is a storage engine …

Query profiling is a useful technique for analyzing the overall performance of a database. Considering that a single mid-to-large sized application can execute numerous queries each and every second, query profiling is an important part of database tuning, both as a proactive measure and in diagnosing problems.  In fact, it can become difficult to determine the exact sources and causes of bottlenecks and sluggish performance without employing some sort of query profiling techniques. This blog will present a few useful query profiling techniques that exploit MariaDB server’s own built-in tools: the Slow Query Log and the Performance Schema.

MariaDB vs. MySQL

Needless to say, the techniques that we’ll be covering here today are likely to be equally applicable to MySQL, due to the close relationship between the two products.

The day that Oracle announced the purchase of Sun back in 2010, Michael “Monty” Widenius …

Although only available as a Release Candidate, MySQL 8 is already proving itself to be a huge leap forward in many regards. Error logging is no exception. The MySQL development team just announced that they have redesigned the error logging subsystem to use a new component architecture.

The redesign will allow the filtering of log events, as well as the routing of error log output to multiple destinations, via the enabling of multiple sink components.  This will make it possible to send error log events to third-party systems for additional formatting and analysis.

In today’s blog, we’ll explore how to employ MySQL 8’s component-based error logging to achieve a variety of logging configurations. Note that all this is specific for MySQL 8 and is not available in earlier versions and also not in MariaDB. However, MariaDB has an option to write the error log to the system “syslog” on systemd-based Linux variants – …