[IMPALA-4970] Record identity of largest latency ExecQueryFInstances() RPC per query

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 2.9.0
• Fix Version/s: Impala 3.1.0
• Component/s: Distributed Exec
• Labels: newbie ramp-up
• Target Version: Product Backlog
• Assignee: Rahul Shivu Mahadev
• Reporter: Henry Robinson
• Created: 22/Feb/17 23:52
• Updated: 19/Jun/18 21:22
• Resolved: 19/Jun/18 21:22

Description

Although we retain the histogram of fragment instance startup latencies, we don't record the identity of the most expensive instance, or the host it runs on. This would be helpful in diagnosing slow query start-up times.