Innodb_write_io_threads is a variable closely related to innodb_read_io_threads
. Set the number of InnoDB threads handling write operations, using innodb_write_io_threads. The innodb_read_io_threads
sets the number of InnoDB threads handling read requests. These variables work with MySQL, Percona, and MariaDB.
256 I/O requests can be in a pending state for each I/O write thread. Setting innodb_write_io_threads to 4, means the system will handle 1024 concurrent asynchronous write I/O requests. InnoDB will attempt to balance the pending I/O requests across all available threads.
InnoDB I/O asynchronous subsystem is controlled by the innodb_use_native_aio variable, which is enabled by default.