Add stackCycle feature for decrease useless connections #1805
+57
−3
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If you are using a connection pool and suddenly handle more traffic than usual, the size of the connection pool increases. And the increased connections will survive because of the wait_timeout setting. (It usually set as 10-30 seconds) Keeping unnecessary connections is not good for running multiple servers.
However, this problem can not be solved because the mysql module only supports round-robin styles. So I added a pool option called stackCycle.