[OAK-6074] Simplify merge logic in LockBasedScheduler

• Type: Task
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.7.3, 1.8.0
• Component/s: segment-tar
• Epic Link: TarMK transaction rate
• Assignee: Andrei Dulceanu
• Reporter: Andrei Dulceanu
• Created: 12/Apr/17 14:10
• Updated: 06/Jul/17 15:34
• Resolved: 27/Apr/17 10:06

Description

The current logic for executing a commit in LockBasedScheduler is unnecessarily intricate, containing separate strategies for optimistic and pessimistic merges. While these would have made sense in a hierarchical, multi-journal approach, when using a single journal file we always end up on the optimistic merge branch, since a commit semaphore is acquired before attempting to merge the commit. The proposal is to remove LockBasedScheduler#optimisticMerge and LockBasedScheduler#pessimisticMerge methods, simplifying the logic inside LockBasedScheduler#execute.