[SPARK-9043] Serialize key, value and combiner classes in ShuffleDependency

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.6.0
• Component/s: Shuffle, Spark Core
• Target Version/s: 1.6.0
• Assignee: Matt Massie
• Reporter: Matt Massie
• Created: 14/Jul/15 21:09
• Updated: 17/May/20 18:31
• Resolved: 11/Sep/15 00:24

Description

ShuffleManager implementations are currently not given type information regarding the key, value and combiner classes. Serialization of shuffle objects relies on them being JavaSerializable, with methods defined for reading/writing the object or, alternatively, serialization via Kryo which uses reflection.

Serialization systems like Avro, Thrift and Protobuf generate classes with zero argument constructors and explicit schema information (e.g. IndexedRecords in Avro have get, put and getSchema methods).

By serializing the key, value and combiner class names in ShuffleDependency, shuffle implementations will have access to schema information when registerShuffle() is called.

Issue Links

• links to: [Github] Pull Request #7403 (massie)