在后端连接激增期间,在启动 ProxySQL 后连接超时(仅限 3.x 版本,在 2.x 版本中无法重现)

Basically, the bug is triggered when ProxySQL has to create a bunch of new connections to the backend, and that backend has TLS enabled. If TLS is disabled between ProxySQL and MySQL backend, such storms are not dangerous. Here are the steps to reproduce this bug. Required Files: proxysql-bug-Docker-compose.tgz 1. Create a ProxySQL+MySQL+sysbech setup with Docker compose. ``` Docker compose -f Docker-compose-MySQL-8.4.yml up

2. Log in to the sysbench container and run the workload using sysbench. ```
Docker exec -it sysbench /bin/bash
[root@c7b4454d5ebb sysbench]# ./connection-only.sh

1. ProxySQL logs will be filled with "Connect timeout" errors. The backend might be shunned. Like the following: ``` proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 828686us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 828686us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 828686us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 828686us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 1512638us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 1512638us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 1512638us proxysql | 2026-09-21 10:42:57 MySrvC.cpp:129:connect_error(): [ERROR] Shunning server MySQL-server:3306 with 5 errors/sec. Shunning for 10 seconds proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 1512638us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 1512638us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 1512638us proxysql | 2026-09-21 10:42:57 mysql_connection.cpp:1441:handler(): [ERROR] Connect timeout on MySQL-server:3306 : exceeded by 1512638us proxysql | 2026-09-21 10:42:57 MySrvC.cpp:129:connect_error(): [ERROR] Shunning server MySQL-server:3306 with 5