tidb_server_connections存在小于0的值

有猫万事足 · 2024 年7 月 1 日 03:41

Connection count metric can be less than the real value

opened 07:14AM - 19 Mar 24 UTC

closed 09:47AM - 22 Mar 24 UTC

type/bug sig/sql-infra severity/moderate affects-7.5 found/community

This issue has similar reason with #42761, because the `conn.Close()` will be ca…lled multiple times :facepalm:. ```go func (s *Server) onConn(conn *clientConn) { ... defer func() { terror.Log(conn.Close()) logutil.Logger(ctx).Debug("connection closed") }() ... } ``` And ```go func (cc *clientConn) Run(ctx context.Context) { defer func() { ... if cc.getStatus() != connStatusShutdown { err := cc.Close() terror.Log(err) } close(cc.quit) }() ``` We have two ways to solve this problem: 1. Don't include any logic in `conn.Close()`. Only have logic in the `sync.Once` inside the `closeConn`. 2. Enhance the code, **don't close the connection for multiple times!** (it's more intuitive for the developers).

7.5.2以前确实有这个bug。但是修复时间看应该7.5.2就没有了。
也许这些错误的数据是在升级时间以前？
不知道是否如此。如果还是错的，在issue里面反馈一下看看。