Stackoverflow error while using H2 database in Multi Threaded Environment
Our Application has service layer querying H2 database and retrieving the resultset.
The service layer connects to the h2 database using opensource clustering middleware "Sequoia" (that offers load balancing and transparent failover) and also manages database connections .
https://sourceforge.net/projects/sequoiadb/
Our service layer has 50 service methods and we have exposed the service methods as EJB's . While Invoking the EJB's we get the response from service (that includes H2 READ) with an average response time of 0.2 secs .
The DAO layer, query the database using Hibernate Criteria and we also use JPA2.0 entity manager to manage datasource.
For Load testing , We created a test class (with a main method) that invokes all the 50 EJB Methods .
50 threads were created and all the threads invoked the test class . The execution was Ok for first run and all the 50 threads succssfully completed invoking 50 EJB methods .
When we triggered the test class again , we encountered "stackoverflowerror".The Detailed stacktrace is shown below
org.h2.jdbc.JdbcSQLException: General error: "java.lang.StackOverflowError" [50000-176]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:344)
at org.h2.message.DbException.get(DbException.java:167)
at org.h2.message.DbException.convert(DbException.java:290)
at org.h2.server.TcpServerThread.sendError(TcpServerThread.java:222)
at org.h2.server.TcpServerThread.run(TcpServerThread.java:155)
at java.lang.Thread.run(Thread.java:784)
Caused by: java.lang.StackOverflowError
at java.lang.Character.digit(Character.java:4505)
at java.lang.Integer.parseInt(Integer.java:458)
at java.lang.Integer.parseInt(Integer.java:510)
at java.text.MessageFormat.makeFormat(MessageFormat.java:1348)
at java.text.MessageFormat.applyPattern(MessageFormat.java:469)
at java.text.MessageFormat.<init>(MessageFormat.java:361)
at java.text.MessageFormat.format(MessageFormat.java:822)
at org.h2.message.DbException.translate(DbException.java:92)
at org.h2.message.DbException.getJdbcSQLException(DbException.java:343)
at org.h2.message.DbException.get(DbException.java:167)
at org.h2.message.DbException.convert(DbException.java:290)
at org.h2.command.Command.executeUpdate(Command.java:262)
at org.h2.jdbc.JdbcPreparedStatement.execute(JdbcPreparedStatement.java:199)
at org.h2.server.TcpServer.addConnection(TcpServer.java:140)
at org.h2.server.TcpServerThread.run(TcpServerThread.java:152)
... 1 more
at org.h2.engine.SessionRemote.done(SessionRemote.java:606)
at org.h2.engine.SessionRemote.initTransfer(SessionRemote.java:129)
at org.h2.engine.SessionRemote.connectServer(SessionRemote.java:430)
at org.h2.engine.SessionRemote.connectEmbeddedOrServer(SessionRemote.java:311)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:107)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:91)
at org.h2.Driver.connect(Driver.java:74)
at org.continuent.sequoia.controller.connection.DriverManager.getConnectionForDriver(DriverManager.java:266)
We then even added a random thread sleep(10-25 secs) between EJB Invocation . The execution was successful thrice (all 50 EJB Invocation) and when we triggered for 4th time ,it failed with above error .
We get to see the above failure even with a thread count of 25 .
The Failure is random and there doesn't seems to be a pattern . Kindly let us know if we have missed any configuration .
Please let me know if you need any additional information . Thanks in Advance for any help .
Technology Stack :
1) Java 1.6
2) h2-1.3.176
3) Sequoia Middleware that manages DB Connection Open and Close.
-Variable Connection Pool Manager
-init pool size 250