[HBASE-18004] getRegionLocations needs to be called once in ScannerCallableWithReplicas#call()

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.0
• Fix Version/s: 2.0.0
• Component/s: Client
• Hadoop Flags: Reviewed
• Assignee: Hua Xiang
• Reporter: Hua Xiang
• Created: 05/May/17 21:19
• Updated: 11/Jul/17 19:19
• Resolved: 11/Jul/17 19:19

Description

Look at this line,
https://github.com/apache/hbase/blob/master/hbase-client/src/main/java/org/apache/hadoop/hbase/client/ScannerCallableWithReplicas.java#L145

It calls getRegionLocations() to get the primary region's locations. It's usage is to figure out table's region replications. Since table's region replication wont be changed until the table is disabled. It is safe to cache this region replication.

Issue Links

• Is contained by: HBASE-18223 Track the effort to improve/bug fix read replica feature