线程一直runable，一直hang在socketRead0处

"Thread-4" daemon prio=10 tid=0x00007f2c6000c000 nid=0x2455 runnable [0x00007f2c55deb000] java.lang.Thread.State: RUNNABLE at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.read(SocketInputStream.java:152) at java.net.SocketInputStream.read(SocketInputStream.java:122) at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:100) at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:143) at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:173) - locked <0x00000007b09ea480> (a com.mysql.jdbc.util.ReadAheadInputStream) at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2954) at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3375) at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3365) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3805) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2478) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2625) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2547) - locked <0x00000007b09dcfb8> (a com.mysql.jdbc.JDBC4Connection) at com.mysql.jdbc.ConnectionImpl.setAutoCommit(ConnectionImpl.java:4874) - locked <0x00000007b09dcfb8> (a com.mysql.jdbc.JDBC4Connection) at com.alibaba.druid.pool.DruidPooledConnection.setAutoCommit(DruidPooledConnection.java:694) at org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:225)

以上是jstack得到的线程状态，多次dump都发现该线程一直不返回，也一直不超时！！！

原提问者GitHub用户Yaccc