[LOG4J2-1121] LoggerConfig performance improvement: remove waitForCompletion and associated fields

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3
• Fix Version/s: 2.4
• Component/s: Core
• Assignee: Remko Popma
• Reporter: Remko Popma
• Created: 13/Sep/15 12:49
• Updated: 12/Sep/20 17:33
• Resolved: 20/Sep/15 08:39

Description

This ticket follows up on LOG4J2-1120. Out of the three changes identified in LOG4J2-1120, only two could be implemented in time for the 2.4 release.

This ticket tracks the remaining work for the third change:

• Since clearAppenders() is only called after all appenders have been stopped, waitForCompletion() may no longer be necessary (unless I am missing something here). If so, the shutdownLock, shutdown and counter fields can be removed. Not incrementing the atomic counters with every event in the hot path should give better performance.

LOG4J2-1120 shows benchmark results that support this.

Issue Links

• causes: LOG4J2-2919 "AsyncAppender is not active" when logging with AsynAppender while the system is reconfigure concurrently
• is related to: LOG4J2-702 LoggerConfig#waitForCompletion is not thread safe
• is related to: LOG4J2-1120 LoggerConfig performance improvements