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Which is the best way to configure MySQL memory usage?
Correctly configuring the use of available memory resources is one of the most important things you have to get right with MySQL for optimal performance and stability. As of MySQL 5.7, the default configuration uses a very limited amount of memory – leaving defaults is one of the worst things you can do.
How does memory allocation per thread work in MySQL?
One more thing, not allper-thread memory allocation is configured by variables. Some of the memory allocation per thread is done by MySQL itself for running complex processes/queries like “stored procedures”and it can take an unlimited amount of memory while running.
Why does MySQL keep swapping out memory?
Without this configuration setting, you might find the OS swapping out portions of MySQL just because it feels it needs to increase the amount of available file cache (which is almost always a wrong choice for MySQL). The next thing when it comes to OS configuration is setting the Out Of Memory killer.
How can I reduce the memory footprint of MySQL?
I simply added a low table_definition_cache (=50) to the default my.cnf and reduced memory footprint from ~500Mb to ~80Mb. This is on a virtual server for development purposes with only one user and a few dozen tables. It was the only option that had a significant effect on memory usage.
Why does MySQL keep running out of memory?
Like other bottlenecks, if your server is constantly running out of memory, you can upgrade by adding more. If you run short of memory, your server will cache data storage (like a hard drive) to act as memory. Database caching slows down your performance.
Which is the best way to improve MySQL performance?
In general, it’s always better to use native MySQL performance enhancement over scripting and configuration files. These methods involve tweaking the MySQL configuration files, writing more efficient database queries, and structuring the database to retrieve data more efficiently.
Is it good to swap out memory in MySQL?
It is fine to have some used space in your swap file, as there are probably parts of the operating system that are unused when MySQL is running, and it’s a good idea to swap them out. What you don’t want is constant swapping going on during the operation, which is easily seen in the “si” and “so” columns in the vmstat output.
Why does MySQL failover from master to slave?
Slave can be arbitrarily behind master in reading or applying changes. If the master crashes, transactions that it has committed might not have been transmitted to any slave. Consequently, failover from master to slave in this case may result in failover to a server that is missing transactions relative to the master.
What do I need to configure MySQL on my computer?
The Config Type option lets you choose between three server configuration types. Development Computer , Server Computer , and Dedicated Computer define whether the server is dedicated solely to running your MySQL database or is going to share the underlying system with other applications.