broken pipe socketexception using mysql persistence

>
> Hi,
>
>
> I'm using stable version 3.9.1.201202031753 PE with a mysql persistence
> config (for all apps and forms).
> When the form runner has been idle for a while (I guess the default of 720
> minutes), I get exceptions in the log telling me of a broken pipe:
>
>
> 2012-04-10 10:38:27,494 ERROR ProcessorService  - Exception at
> oxf:/apps/fr/persistence/mysql/search.xpl (executing XSLT transformation)
> java.net.SocketException: Broken pipe
>         at java.net.SocketOutputStream.socketWrite0(Native Method)
>         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:3345)
>         at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1983)
>         at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2163)
>         at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2618)
>         at
> com.mysql.jdbc.ConnectionImpl.setAutoCommit(ConnectionImpl.java:5000)
>         at
> org.apache.commons.dbcp.DelegatingConnection.setAutoCommit(DelegatingConnection.java:371)
>         at
> org.apache.commons.dbcp.DelegatingConnection.setAutoCommit(DelegatingConnection.java:371)
>         at
> org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.setAutoCommit(PoolingDataSource.java:328)
>         at
> org.orbeon.oxf.processor.DatabaseContext.setConnectionProperties(DatabaseContext.java:124)
>         at
> org.orbeon.oxf.processor.DatabaseContext.getConnection(DatabaseContext.java:62)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessorInterpreterContext.getConnection(SQLProcessorInterpreterContext.java:334)
>         at
> org.orbeon.oxf.processor.sql.interpreters.QueryInterpreter.end(QueryInterpreter.java:173)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$InterpreterContentHandler.endElement(SQLProcessor.java:540)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$ForwardingContentHandler.endElement(SQLProcessor.java:635)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$InterpreterContentHandler.endElement(SQLProcessor.java:542)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$ForwardingContentHandler.endElement(SQLProcessor.java:635)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$InterpreterContentHandler.endElement(SQLProcessor.java:542)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$ForwardingContentHandler.endElement(SQLProcessor.java:635)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$InterpreterContentHandler.endElement(SQLProcessor.java:542)
>         at
> org.orbeon.oxf.processor.sql.SQLProcessor$RootInterpreter.endElement(SQLProcessor.java:290)
>         at org.orbeon.oxf.xml.SAXStore.replay(SAXStore.java:288)
>         at org.orbeon.oxf.xml.SAXStore.replay(SAXStore.java:202)
> ... and so on
>
>
>
> When this happens, I also get "no results" (empty table) in the browser,
> instead of an error message.
>
> When searching about the exception, I came upon this:
> http://mikeschubert.com/2006/08/03/javanetsocketex/
>
> I think this might be what's happening: orbeon has a connection to the
> database because of doing a query without commiting it, time passes, and the
> connection gets broken. When refreshing the browser a few times after
> waiting a minute, things start to work again, as a new connection is made.
> However, in a production environment, this cannot be tolerated.
>
> I guess I could circumvent the problem doing something like (tomcat
> configuration of the jdbc resource):
>
>
> <Resource name="jdbc/mysqldb"
>           auth="Container"
>           type="javax.sql.DataSource"
>           driverClassName="com.mysql.jdbc.Driver"
>           url="jdbc:mysql://localhost:3306/D01?autoReconnect=true"
>           username="tomcat"
>           password="tomcat"
>           maxActive="20"
>           maxIdle="30"
>           maxWait="-1"
> />
>
> Keeping maxwait at -1 means wait indefinitely, so all connections can
> remain open. But this would probably deteriorate the db connection after a
> while.
>
>
>
> Am I completely wrong about what this error means, or does the orbeon
> mysql persistence service forget to commit its queries? (I know, it's
> strange having to commit queries)
> Will there be a fix?
>
>
> Thank you,
>
>
>
> Koen Vanderkimpen
>
> Connect:
>
>
>
>
>
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