[SPARK-22692] Reduce the number of generated mutable states

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.0
• Fix Version/s: 2.3.0
• Component/s: SQL
• Assignee: Marco Gaido
• Reporter: Marco Gaido
• Created: 05/Dec/17 10:35
• Updated: 31/Jan/18 07:59
• Resolved: 30/Jan/18 09:53

Description

A large number of mutable states can cause a error during code generation due to reaching the constant pool limit. There is an ongoing effort on SPARK-18016 to fix the problem, nonetheless we can also alleviate it avoiding to create a global variables when they are not needed.

Therefore I am creating this umbrella ticket to track the elimination of usage of global variables where not needed. This is not a duplicate or an alternative to SPARK-18016: this is a complementary effort which can help together with it to support wider datasets.

Sub-Tasks

• Avoid the generation of useless mutable states by datetime functions: Resolved
• Avoid the generation of useless mutable states in complexTypeCreator and predicates: Resolved
• Avoid the generation of useless mutable states by regexp functions: Resolved
• Avoid the generation of useless mutable states by scalaUDF: Resolved
• Avoid the generation of useless mutable states by objects functions: Resolved
• Avoid the generation of useless mutable states by GenerateMutableProjection: Resolved
• Avoid the generation of useless mutable states by GenerateUnsafeProjection: Resolved
• Avoid the generation of useless mutable states by GenerateSafeProjection: Resolved
• Avoid the generation of useless mutable states by SortMergeJoin: Resolved
• Introduce reusable mutable states: Resolved
• Avoid the creation of mutable states in addReferenceObj: Resolved
• Avoid the generation of useless mutable states by Stack function: Resolved