Large scale multithreading operations on transactions , Sometimes open a link , Will wait , At this time, if the database timeout is set too short , It could happen , Data links are automatically released , Of course, it's not good to set it too big , slow SQL Or other factors cause the link to be too long , Causing the whole system to slow down , Even hung up .
SO, Set the timeout appropriately .
I checked a lot of information on the Internet , Most solutions are written too complex , In fact, as long as you set the waiting timeout OK 了
problem ：mq Consumption time mysql From time to time mysql gone away
terms of settlement ： Because this is the function of payment So set the waiting time 12 Hours , Avoid disconnection when you don't pay at night .
Setup method ：
SHOW GLOBAL VARIABLES LIKE '%timeout%'
SET GLOBAL wait_timeout=43200