Hi Bront,

Is there a stack trace in the labkey.log file? It would help in determining if it's the same underlying scenario as issue 21294, or something unrelated.

Thanks,
Josh

Yes, please share the stack trace to help us track down the underlying cause.

I added a workaround for this issue in 14.3, as part of the improvements documented in issue #20880. Once you move to 14.3 let us know if you still see the problem.

Adam

Here's are a couple of recent errors...

Thanks,

bront


ERROR Table 2014-11-11 14:43:21,393 DavCrawler : SQL Exception
org.postgresql.util.PSQLException: Cannot change transaction isolation level in the middle of a transaction.
    at org.postgresql.jdbc2.AbstractJdbc2Connection.setTransactionIsolation(AbstractJdbc2Connection.java:940)
    at sun.reflect.GeneratedMethodAccessor155.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.tomcat.jdbc.pool.ProxyConnection.invoke(ProxyConnection.java:126)
    at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:109)
    at org.apache.tomcat.jdbc.pool.DisposableConnectionFacade.invoke(DisposableConnectionFacade.java:80)
    at com.sun.proxy.$Proxy2.setTransactionIsolation(Unknown Source)
    at org.labkey.api.data.ConnectionWrapper.setTransactionIsolation(ConnectionWrapper.java:306)
    at org.labkey.core.dialect.PostgreSql84Dialect.configureToDisableJdbcCaching(PostgreSql84Dialect.java:1508)
    at org.labkey.api.data.ExecutingSelector$ExecutingResultSetFactory.getResultSet(ExecutingSelector.java:297)
    at org.labkey.api.data.BaseSelector.handleResultSet(BaseSelector.java:244)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:94)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:141)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:125)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:120)
    at org.labkey.search.model.SavePaths.getPaths(SavePaths.java:289)
    at org.labkey.search.model.DavCrawler.findSomeWork(DavCrawler.java:523)
    at org.labkey.search.model.DavCrawler$1.run(DavCrawler.java:490)
ERROR Table 2014-11-11 14:43:21,393 DavCrawler : SQL [31778]
    SELECT Path, LastCrawled, NextCrawl
    FROM search.CrawlCollections
    WHERE NextCrawl < ? AND (LastCrawled IS NULL OR LastCrawled < ?) ORDER BY NextCrawl
    LIMIT 100
    ?[1] Tue Nov 11 14:43:21 EST 2014
    ?[2] Tue Nov 11 14:21:00 EST 2014

    org.labkey.api.data.ExecutingSelector$ExecutingResultSetFactory.handleSqlException(ExecutingSelector.java:414)
    org.labkey.api.data.BaseSelector.handleResultSet(BaseSelector.java:253)
    org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:94)
    org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:141)
    org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:125)
ERROR DavCrawler 2014-11-11 14:43:21,393 DavCrawler : Unexpected error
org.springframework.jdbc.UncategorizedSQLException: ExecutingSelector; uncategorized SQLException for SQL []; SQL state [25001]; error code [0]; Cannot change transaction isolation level in the middle of a transaction.; nested exception is org.postgresql.util.PSQLException: Cannot change transaction isolation level in the middle of a transaction.
    at org.springframework.jdbc.support.SQLStateSQLExceptionTranslator.translate(SQLStateSQLExceptionTranslator.java:124)
    at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.translate(SQLErrorCodeSQLExceptionTranslator.java:322)
    at org.labkey.api.data.ExceptionFramework$1.translate(ExceptionFramework.java:38)
    at org.labkey.api.data.ExceptionFramework$1.translate(ExceptionFramework.java:32)
    at org.labkey.api.data.ExecutingSelector$ExecutingResultSetFactory.handleSqlException(ExecutingSelector.java:416)
    at org.labkey.api.data.BaseSelector.handleResultSet(BaseSelector.java:253)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:94)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:141)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:125)
    at org.labkey.api.data.ExecutingSelector.getResultSet(ExecutingSelector.java:120)
    at org.labkey.search.model.SavePaths.getPaths(SavePaths.java:289)
    at org.labkey.search.model.DavCrawler.findSomeWork(DavCrawler.java:523)
    at org.labkey.search.model.DavCrawler$1.run(DavCrawler.java:490)
Caused by: org.postgresql.util.PSQLException: Cannot change transaction isolation level in the middle of a transaction.
    at org.postgresql.jdbc2.AbstractJdbc2Connection.setTransactionIsolation(AbstractJdbc2Connection.java:940)
    at sun.reflect.GeneratedMethodAccessor155.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.tomcat.jdbc.pool.ProxyConnection.invoke(ProxyConnection.java:126)
    at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:109)
    at org.apache.tomcat.jdbc.pool.DisposableConnectionFacade.invoke(DisposableConnectionFacade.java:80)
    at com.sun.proxy.$Proxy2.setTransactionIsolation(Unknown Source)
    at org.labkey.api.data.ConnectionWrapper.setTransactionIsolation(ConnectionWrapper.java:306)
    at org.labkey.core.dialect.PostgreSql84Dialect.configureToDisableJdbcCaching(PostgreSql84Dialect.java:1508)
    at org.labkey.api.data.ExecutingSelector$ExecutingResultSetFactory.getResultSet(ExecutingSelector.java:297)
    at org.labkey.api.data.BaseSelector.handleResultSet(BaseSelector.java:244)
    ... 7 more

We are also running Ubuntu 14.04 and PostgreSQL 9.3.5.

thanks,

bront