[IMPALA-9687] Plans for Kudu can contains hosts > num of Impala nodes

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Impala 4.0.0
• Component/s: Frontend
• Labels: kudu ramp-up
• Epic Color: ghx-label-14
• Assignee: Akos Kovacs
• Reporter: Csaba Ringhofer
• Created: 23/Apr/20 23:37
• Updated: 09/Jan/21 07:59
• Resolved: 09/Jan/21 07:59

Description

Started a cluster with 1 coordinator and 1 executor:

bin/start-impala-cluster.py -c 1 --use_exclusive_coordinator -s 2

Queries on Kudu tables still contained hosts=3, while all other table types had hosts=1.

explain select * from functional_kudu.alltypestiny;
Result:
...
F00:PLAN FRAGMENT [RANDOM] hosts=3 instances=3
...

The numbers in the plan are only estimates, the summary after the query contained 1 host.