Hi,
After you run the query you need to look at the query profile to analyse the complete memory.
look for “Per node peak memory usage” in the profile to understand how much memory each host or impala daemon used to run this query.
For above snippet from your side it looks like this query has the 3gb max limit to run the query, this can be set at session level or in impala admission control pool. If you provide the complete query profile i think we can get more details.
Regards,
Chethan YM