[HBASE-24298] Reduce cpu load of locating region especially in batch mode.

• Type: Bug
• Status: Patch Available
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.2.12
• Component/s: Performance
• Assignee: star
• Reporter: star
• Created: 01/May/20 11:46
• Updated: 31/Dec/21 13:51

Description

Binary search is used to speedup the process of locating region. It is already fast enough, while cpu of HBASE client becomes the bottleneck when doing TCSB benchmark. We can make the process of locating region faster to reduce cpu load in some special cases , which however is our common case in production environment.  It is the case: 

        1. Predefined splits in uniform distribution.
 
        2. Load data in batch mode.

The optimization is very simple, just to contract range of binary search. Initially,  record all startIndex and endIndex of first or two bytes of keys. When a region key comes, find the contracted startIndex and endIndex of the key. Then return to normal binary search process with the specified startIndex and endIndex. 

Then we can ideally reduce cpu to 1/8 with 1 byte or 1/16 with 2 bytes.