[FLINK-25968] Possible class leaks in flink-table / sql modules

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.15.0
• Fix Version/s: 1.15.0
• Component/s: Table SQL / Planner, Table SQL / Runtime
• Assignee: Francesco Guardiani
• Reporter: Yun Gao
• Created: 07/Feb/22 08:22
• Updated: 10/Mar/22 08:41
• Resolved: 10/Mar/22 08:37

Description

This is the umbrella issues for possible class leaks in flink-table / sql planner and runtimes.

Currently for a flink cluster, the flink classes are loaded by the system ClassLoader while each job would have separate user ClassLoaders. In this case, if some class loaded by the system ClassLoader has static variables that reference the classes loaded by the user ClassLoaders, the user ClassLoaders would not be able to be released, which might cause class leak in some way.

Issue Links

• is related to: FLINK-18356 flink-table-planner Exit code 137 returned from process

Sub-Tasks

• org.apache.flink.table.runtime.generated.CompileUtils might cause class leaks: Closed
• org.apache.flink.table.planner.plan.nodes.exec.serde.JsonSerdeUtil#OBJECT_MAPPER_INSTANCE might cause class leaks: Closed
• org.apache.calcite.rel.metadata.JaninoRelMetadataProvider#HANDLERS might cause class leaks: Closed