[FLINK-9014] Adapt BackPressureStatsTracker to work with credit-based flow control

• Type: Sub-task
• Status: Closed
• Priority: Critical
• Resolution: Not A Problem
• Affects Version/s: 1.5.0
• Fix Version/s: 1.5.0
• Component/s: Runtime / Network, Runtime / Web Frontend
• Assignee: Piotr Nowojski
• Reporter: Nico Kruber
• Created: 16/Mar/18 17:53
• Updated: 23/Mar/18 15:29
• Resolved: 23/Mar/18 15:29

Description

The BackPressureStatsTracker relies on sampling threads being blocked in LocalBufferPool#requestBufferBuilderBlocking to indicate backpressure but with credit-based flow control, we are also back-pressured if we did not get any credits (yet).