[GEARPUMP-78] Support DAG with cycles

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: streaming
• Assignee: Manu Zhang
• Reporter: Manu Zhang
• Created: 21/Apr/16 08:22
• Updated: 29/May/16 06:35

Description

imported from https://github.com/gearpump/gearpump/issues/1231 on behalf of clockfly,

DAG with loop should not be called DAG

We see use cases that require a feedback channel.
The challengues will be:

1. how to support the low watermark clock? As the clock is defined recursively?
2. How to support back-pressure. DAG with loop can possiblely create a live-lock issue. With each processor wait for acks from other processor before sending acks.

Issue Links

• depends upon: GEARPUMP-114 Dead loop in graph with cycles