[IMPALA-5147] Add the ability to exclude coordinators from query execution

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Impala 2.9.0
• Component/s: Backend
• Epic Color: ghx-label-7
• Assignee: Dimitris Tsirogiannis
• Reporter: Dimitris Tsirogiannis
• Created: 31/Mar/17 18:14
• Updated: 08/Jun/17 20:30
• Resolved: 01/May/17 17:57

Description

The fix for IMPALA-4041 added the ability to limit the set of nodes that can coordinate Impala queries and hence receive catalog updates. However, with this change coordinators can and will still participate in query execution. That may introduce in some cases significant load in the coordinator node. To address this issue, we should introduce another flag, termed is_executor, to exclude certain nodes from participating in query execution.