DriverManager.getConnection is too slow in linux

[오종현 남]

Hello, I'm Jack and using MySQL for my study.

i'd like to ask a question i found today.

before get started,

my environment like this.


MySQL server
version : 5.2.8-MariaDB
os: Windows ??

Java Application Server
os : linux 2.6.32-504.e16.x86_64
connector version : 5.1.36
jdk ver : 1.7.72


so the problem is,

it takes more than 4seconds on this statement to get connection.

DriverManager.getConnection(url,id,pass);

but the strange thing is, if i run this at windows machine,

it takes only 200ms.

while this hanging, i capture thead dump and found out that socket read is holding.

i'd like to reduce this 'making connection time' and understand why this happens.


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 <0x000000058203d870> (a com.mysql.jdbc.util.ReadAheadInputStream)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2923)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:560)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1014)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2249)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2280)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2079)
- locked <0x0000000581da3a68> (a com.mysql.jdbc.JDBC4Connection)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:794)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:400)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
at java.sql.DriverManager.getConnection(DriverManager.java:571)
at java.sql.DriverManager.getConnection(DriverManager.java:215)
at jTest.MySQLDBConnector.initializeDataBase(MySQLDBConnector.java:48)
at jTest.JavaTest.main(JavaTest.java:15)





Thanks for your help in advance.
-Jack