[YARN-6738] LevelDBCacheTimelineStore should reuse ObjectMapper instances

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.9.0, 3.0.0-alpha4, 2.8.2
• Component/s: timelineserver
• Hadoop Flags: Reviewed
• Assignee: Zoltan Haindrich
• Reporter: Zoltan Haindrich
• Created: 23/Jun/17 13:35
• Updated: 28/Jun/17 06:01
• Resolved: 27/Jun/17 22:19

Description

Using TezUI sometimes times out...and the cause of it was that the query was quite large; and the leveldb handler seems like recreates the ObjectMapper for every read - this is unfortunate; since the ObjectMapper have to rescan the class annotations which may take some time.

Keeping the objectmapper reduces the ATS call time from 17 seconds to 3 seconds for me...which was enough to get my tez-ui working again