In that case, my suggestion is to check for HS2 logs to try to find any queries that takes time to compile. Because HS2 currently can only compile one query at a time, if you have a query that takes a while to compile, it will lock out HS2 and other requests will have to wait. I am not sure if it is the cause, but worth to check the HS2 log. Look for the following example: Completed compiling command(queryId=hive_20170227192424_ee0c5216-bef5-456a-934e-212aabe55b75); Time taken: 0.191 seconds and check if any Time taken values are too big around the time when issue happens. ... View more