[HBASE-17332] Replace HashMap to Array for DataBlockEncoding.idToEncoding

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4.0, 2.0.0
• Fix Version/s: 1.4.0, 2.0.0
• Assignee: Lijin Bin
• Reporter: Lijin Bin
• Created: 19/Dec/16 02:27
• Updated: 20/Dec/16 10:03
• Resolved: 20/Dec/16 05:01

Description

Array is faster than HashMap also no need to autoboxing.
I can see the DataBlockEncoding#getDataBlockEncoderById is a hot method if enable encoding in my perf test(Random read, all data cache in LruBlockCache).