[ZOOKEEPER-3110] Improve the closeSession throughput in PrepRequestProcessor

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 3.6.0, 3.5.5
• Component/s: quorum
• Labels: pull-request-available
• Assignee: Fangmin Lv
• Reporter: Fangmin Lv
• Created: 07/Aug/18 00:17
• Updated: 20/May/19 17:50
• Resolved: 08/Aug/18 04:30

Description

On leader every expired global session will add 3 lines of logs, which is pretty heavy and if the log file is more than a few GB, the log for the closeSession in PrepRequestProcessor will slow down the whole ensemble's throughput. 

From some use case, we found the prep request processor will be a bottleneck when there are constantly high number of expired session or closing session explicitly.

This JIra is going to remove one of the useless log when prepare close session txns, which should give us higher throughput during processing large number of expire sessions.

Issue Links

• links to: GitHub Pull Request #591