Debugging Impala query that consistently hangs

[Piyush Narang]

Hi folks,

I have a query that I’m running on Impala that seems to consistently stop 
making progress after reaching 45-50%. It stays at that split number for a 
couple of hours (before I cancel it).  I don’t see any progress on the summary 
page either. I’m running 2.11.0-cdh5.14.0 RELEASE (build 
d68206561bce6b26762d62c01a78e6cd27aa7690). It seems to not be making progress 
from an exchange hash step.
Has anyone run into this in the past? Any suggestions on what’s the best way to 
debug this? (I could take stack dumps on the coordinator / workers, but not 
sure if there’s any other way).

Thanks,

-- Piyush