问题
I am facing error processing on some widgets while loading dashboards on my applictaion randomly.
In the catalina.log, for one or two widgets, it is showing :
mondrian.olap.MondrianException: Mondrian Error:Internal error: Query required more than 12 iterations
and for one or two widgets, it is showing :
java.lang.NullPointerException
But if I select the same dashboard again, it'll run perfectly. It is behaving very flakily.
To fix the iteration error, I did :
mondrian.rolap.evaluate.MaxEvalDepth to 50 in mondrian.properties , which is 10 by default
This got me rid of iteration errors, but resulted in a java.lang.NullPointerException for other two widgets permanently except for default loading of dashboard. Due to which, I considered that the mondrian cache is getting overflowed or corrupted.
To fix this, I set maxElementsInMemory to 20000 for mondrian-catalog-cache in ehcache.xml, which is 30 by default
which solved the continous occurrennce of java.lang.NullPointerException,
but situation again is same , i.e. dashboards are behaving flaky as earilier.
As i have seen on forums many people have faced similar problems.
来源：https://stackoverflow.com/questions/29755017/randon-error-processing-on-pentaho-cde-dashboard-for-mdx-query-widget