What is the optimal value for max_user_connections?

Question

MySQL

What is the optimal value for max_user_connections and does it depend on max_connections? Memory 32 Gb, InnoDB by default.

Answer 1

max_user_connections - maximum number of sessions for 1 user. configured for each user separately. Those. user1 -5 user2 -10 wordpress - 100.
max_connections - maximum number of total sessions per server.
for example, we have 2 users, each has max_user_connections=100. Muscle settings are default, max_connections = 151. 1 user has created 100 connections, the rest are sleeping. This first user tries to raise the 101st connection, gets a thump (Error: 1203 SQLSTATE: 42000 (ER_TOO_MANY_USER_CONNECTIONS)) - personal connections have run out. The second one wakes up, starts to raise its connections (the first one still "ate" 100 pieces). 49 - OK, 50 - OK, 51 - OK, 52 - Error: 1040 SQLSTATE: 08004 (ER_CON_COUNT_ERROR), total number of connections has ended.
those. Answering your questions:
1. Who knows, depends on your application.
2. yes, setting more than max_connection to no purpose, the general restriction will work.
general advice - let the server run for at least a week, then do show status like '%onn%';
see what's in the Max_used_connections field and see if there are Connections_errors. If the first value is far from max_connections (and there are no / almost no errors), this parameter can be reduced - free up memory.