MySQL optimization small case: key_buffer_size

Key_buffer_size is one of the most influential parameters for MyISAM table performance, and the following is a configuration of the primary storage engine server with MyISAM:

mysql> SHOW VARIABLES like '%key_buffer_size% ';

　　

See the usage of key_buffer_size below:

Mysql> SHOW GLOBAL STATUS like '%key_read% '; +-------------------+-----------------+| Variable_name     | Value           |+-------------------+-----------------+| key_read_requests | 2454354135490   | | Key_reads         | 23490           |+-------------------+-----------------+2 rows in Set (0.00 sec)

Altogether there were key_read_requests index requests, which took place altogether key_reads times physical IO

key_reads/key_read_requests≈0.1% the following is better.

MySQL optimization small case: key_buffer_size