[FLINK-3267] Disable reference tracking in Kryo fallback serializer

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 0.10.1
• Fix Version/s: 1.0.0
• Component/s: Runtime / Task
• Assignee: Stephan Ewen
• Reporter: Stephan Ewen
• Created: 20/Jan/16 15:26
• Updated: 25/Jan/16 14:25
• Resolved: 25/Jan/16 14:25

Description

Kryo runs extra logic to track and resolve repeated references to the same object (similar as JavaSerialization)

We should disable reference tracking

• reference tracking is costly
• it is virtually always unnecessary in the datatypes used in Flink
• most importantly, it is inconsistent with Flink's own serialization (which does not do reference tracking)
• It may have problems if elements are read in a different order than they are written.