【 使用环境 】准生产环境
【 OB or 其他组件 】OceanBase Binlog 服务
【 使用版本 】4.2.5-100000042025052216
【问题描述】obproxy连接数暴涨，初步排查是因为ob租户Binlog 服务状态异常，咱们自研的数据同步工具不断重连obproxy，最终导致连接数满了，业务连接不上数据库
【复现路径】
【附件及日志】
logproxy.log中的error日志：
[2025-09-10 10:22:07.723162] [error] ob_mysql_packet.cpp(81): Failed to receive mysql packet because of poll.revents & POLLERR
[2025-09-10 10:22:07.723202] [error] mysql_protocol.cpp(83): Failed to receive handshake packet from: ./run/cv74u785br/binlog_instance.socket, error: 11(Resource temporarily unavailable)
[2025-09-10 10:22:07.723207] [error] instance_client.cpp(62): Failed to login binlog instance, is_local: true, addr: ./run/cv74u785br/binlog_instance.socket, exceed uds len limit: false
[2025-09-10 10:22:07.723211] [error] instance_client.cpp(42): Failed to connect to instance: cv74u785br, server addr: ./run/cv74u785br/binlog_instance.socket
[2025-09-10 10:22:07.723213] [error] database_protocol.cpp(3688): Failed to detect binlog instance: cv74u785br
[2025-09-10 10:22:07.723223] [error] ob_mysql_packet.cpp(140): Failed to send packet, error: 32(Broken pipe)
[2025-09-10 10:22:07.723225] [error] mysql_protocol.cpp(224): Failed to send query packet to server: ./run/cv74u785br/binlog_instance.socket
[2025-09-10 10:22:07.723226] [error] database_protocol.cpp(3433): Failed to show binlog dumplist for instance:cv74u785br
[2025-09-10 10:22:08.661551] [error] io.cpp(188): Failed to connect to server: ./run/cv74u785br/binlog_instance.socket(server_sun.sun_path: ./run/cv74u785br/binlog_instance.socket), error: 111(Connection refused)
[2025-09-10 10:22:08.661580] [error] mysql_protocol.cpp(66): Failed to connect to server: ./run/cv74u785br/binlog_instance.socket
[2025-09-10 10:22:08.661583] [error] instance_client.cpp(62): Failed to login binlog instance, is_local: true, addr: ./run/cv74u785br/binlog_instance.socket, exceed uds len limit: false
[2025-09-10 10:22:08.661585] [error] instance_client.cpp(42): Failed to connect to instance: cv74u785br, server addr: ./run/cv74u785br/binlog_instance.socket
[2025-09-10 10:22:08.661587] [error] database_protocol.cpp(3688): Failed to detect binlog instance: cv74u785br
[2025-09-10 10:22:08.661593] [error] ob_mysql_packet.cpp(140): Failed to send packet, error: 9(Bad file descriptor)
[2025-09-10 10:22:08.661594] [error] mysql_protocol.cpp(224): Failed to send query packet to server: ./run/cv74u785br/binlog_instance.socket
[2025-09-10 10:22:08.661596] [error] database_protocol.cpp(3433): Failed to show binlog dumplist for instance:cv74u785br
