Grails - Broken Pipe and Cannot release connection

In one of my grails applications, I was getting the following exception often,

java.net.SocketException: Broken pipe
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:109)
at java.net.SocketOutputStream.write(SocketOutputStream.java:153)
at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:82)
at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:140)
at com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3832)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2471)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2651)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2734)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2322)
at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:96)
at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:96)
at org.grails.datastore.gorm.GormStaticApi$_methodMissing_closure2.doCall(GormStaticApi.groovy:108)
at grails.plugin.cache.web.filter.PageFragmentCachingFilter.doFilter(PageFragmentCachingFilter.java:195)
at grails.plugin.cache.web.filter.AbstractFilter.doFilter(AbstractFilter.java:63)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:722)
2013-07-21 12:28:16,794 [http-bio-80-exec-7] ERROR util.JDBCExceptionReporter  - Already closed.
2013-07-21 12:28:16,794 [http-bio-80-exec-7] ERROR util.JDBCExceptionReporter  - Already closed.
2013-07-21 12:28:16,807 [http-bio-80-exec-7] ERROR servlet.GrailsDispatcherServlet  - HandlerInterceptor.afterCompletion threw exception
org.hibernate.exception.GenericJDBCException: Cannot release connection
at grails.plugin.cache.web.filter.PageFragmentCachingFilter.doFilter(PageFragmentCachingFilter.java:195)
at grails.plugin.cache.web.filter.AbstractFilter.doFilter(AbstractFilter.java:63)
at grails.plugin.cache.web.filter.PageFragmentCachingFilter.doFilter(PageFragmentCachingFilter.java:195)
at grails.plugin.cache.web.filter.AbstractFilter.doFilter(AbstractFilter.java:63)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:722)
Caused by: java.sql.SQLException: Already closed.
at org.apache.commons.dbcp.PoolableConnection.close(PoolableConnection.java:114)
at org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.close(PoolingDataSource.java:191)
... 7 more

The reason was the database connections in the pool was not used for some time and the connection got closed, and when the application tries to use that it was throwing the exception.

The solution worked to me is

Just added 3 properties into my DataSource.groovy file as follows,

dbCreate = "update" // one of 'create', 'create-drop','update'

url = "jdbc:mysql://localhost/mydb?useUnicode=yes&characterEncoding=UTF-8"

username = "root"

password = "pwd"

properties {

        validationQuery = "select 1"

        testWhileIdle = true

        testOnBorrow = true

 }

you can find more information on this properties at http://commons.apache.org/proper/commons-dbcp/configuration.html

One more reason for the same problem could be double pooling, if you have configured your connection from application server (JNDI), please ensure you are not pooling the connections both in application server and grails application. Just remove one of the pooling to solve the issue.