[SPARK-25074] Implement maxNumConcurrentTasks() in MesosFineGrainedSchedulerBackend

• Type: Task
• Status: Resolved
• Priority: Minor
• Resolution: Incomplete
• Affects Version/s: 2.4.0
• Component/s: Spark Core
• Labels: bulk-closed
• Target Version/s: 3.0.0
• Assignee: Unassigned
• Reporter: Xingbo Jiang
• Created: 09/Aug/18 12:32
• Updated: 25/May/21 01:49
• Resolved: 25/May/21 01:42

Description

We added a new method `maxNumConcurrentTasks()` to `SchedulerBackend` to get the max number of tasks that can be concurrent launched currently. However the method is not implemented in `MesosFineGrainedSchedulerBackend`, so submit a job containing barrier stage shall always fail fast with `MesosFineGrainedSchedulerBackend` resource manager.