wait
When an operation, such as acquiring a lock, mutex, or latch, cannot be completed immediately, InnoDB pauses and tries again. The mechanism for pausing is elaborate enough that this operation has its own name, the wait. Individual threads are paused using a combination of internal InnoDB scheduling, operating system wait() calls, and short-duration spin loops.
On systems with heavy load and many transactions, you might use the output from the SHOW INNODB STATUS command to determine whether threads are spending too much time waiting, and if so, how you can improve concurrency.
See also concurrency.
See also latch.
See also lock.
See also mutex.
See also spin.