[FLINK-4616] Kafka consumer doesn't store last emmited watermarks per partition in state

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 1.1.1
• Component/s: Kafka Connector
• Assignee: Roman Maier
• Reporter: Yuri Makhno
• Created: 13/Sep/16 14:14
• Updated: 13/Feb/17 16:07
• Resolved: 13/Feb/17 14:59

Description

Kafka consumers stores in state only kafka offsets and doesn't store last emmited watermarks, this may go to wrong state when checkpoint is restored:

Let's say our watermark is (timestamp - 10) and in case we have the following messages queue results will be different after checkpoint restore and during normal processing:

A(ts = 30)
B(ts = 35)
------ checkpoint goes here
C(ts=15) – this one should be filtered by next time window
D(ts=60)

Issue Links

• links to: GitHub Pull Request #3031