[FLINK-19876] Latency metrics can merge chain task latency metrics to reduce the number of latency metrics

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Component/s: Runtime / Metrics
• Assignee: Unassigned
• Reporter: zlzhang0122
• Created: 29/Oct/20 08:40
• Updated: 30/Oct/20 06:29
• Resolved: 30/Oct/20 06:29

Description

In latency metrics report, each operator will report themselves latency metics, but actually the communication between chain operators which in one task is very fast and the latency can be ignored.So maybe we can merge the chain operator latency metrics into one to decrease the number of it.

For example, if source operator and downstream flat Map operator has been chained, now it will report the latency metrics separately, while we can merge it and make them report their latency metrics only once.