MySQL Server Status Variables

MySQL Server Status Variables provide valuable insights into the health and performance of your MySQL server. They give you real-time statistics on server activities, allowing you to monitor operations without affecting the server’s performance.

For more detailed information on these variables, including crucial InnoDB data and buffer specifics, refer to the MySQL Server Status Variable Reference.

To list all status variables, use:

For a more specific list, filter with LIKE:

Here are some key status variables to pay attention to:

• Threads_connected – Indicates the number of currently open connections. A high value could suggest too many simultaneous connections, which might overwhelm the server.

• Queries – Shows the total number of queries the server has handled. A sudden spike might indicate a potential issue.

• Innodb_buffer_pool_reads – Reflects the number of logical reads that InnoDB could not satisfy from the buffer pool, requiring a disk read. High values might indicate insufficient buffer pool size.

• Connections – Counts the total number of connection attempts (successful and unsuccessful) to the MySQL server. Frequent unsuccessful attempts might suggest authentication issues or potential security threats.

• Uptime – Displays the number of seconds the server has been up. Frequent restarts might indicate underlying issues that need investigation.

To clear accumulated status variable data and get fresh metrics, use:

This command resets most status variables to zero, giving you a clean slate for performance monitoring and troubleshooting. It's useful when you want to focus on the server's behavior from a specific point in time.