Cause
The expanded tree cache ran out of space, preventing completion of the query.
The expanded tree cache stores XML fragments during query processing. The expanded tree cache must be large enough to hold a copy of all expanded XML fragments needed concurrently during query evaluation. Depending on what the query does and how it is constructed, the set of concurrent fragments may not include every fragment used by the query.
Response
This error may be addressed by modifying your query or your cache configuration.
Tune your query to require fewer expanded XML fragments. For example, tune the query to return fewer results or paginate the results.
Tune your query to require fewer concurrent cached fragments.
Increase the size of the expanded tree cache, using the setting under Groups > Default > Configure. Since increasing the cache size may strain other system resources, you should first attempt to modify or tune your query.
If the error occurs only when processing large documents, consider fragmenting your content.
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