[AURORA-1829] Expose stats on preemptor BiCache expirations

• Type: Task
• Status: Reviewable
• Priority: Minor
• Resolution: Unresolved
• Component/s: Scheduler
• Labels: newbie
• Epic Link: Missing Scheduler Stats
• Assignee: Mehrdad Nurolahzade
• Reporter: Mehrdad Nurolahzade
• Created: 23/Nov/16 19:16
• Updated: 04/May/17 19:08

Description

We have no visibility into whether reservations made by preemption are actually consumed or simply expire.

We are currently collecting stats for the size of preemption/reservation BiCache. We could additionally collect (a) cache expiration stats and (b) reservation entry removals in TaskSchedulerImpl.taskChanged() to monitor overall preemption effectiveness.