[HBASE-20229] ConnectionImplementation.locateRegions() returns duplicated entries when region replication is on

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0
• Assignee: Toshihiro Suzuki
• Reporter: Toshihiro Suzuki
• Created: 20/Mar/18 08:51
• Updated: 01/Aug/18 06:20
• Resolved: 29/Mar/18 17:25

Description

The issue is when region replication is on, ConnectionImplementation.locateRegions() returns duplicated entries.

In the test in my patch, the table should have 1 primary region + 2 secondaries, but ConnectionImplementation.locateRegions() returns 9 regions. Every region repeats 3 times (3 = replicas count).

I think this is because the following code calls locateRegion() even for replica regions and then the result triples.

    for (RegionInfo regionInfo : regions) {
      RegionLocations list = locateRegion(tableName, regionInfo.getStartKey(), useCache, true);
      if (list != null) {
        for (HRegionLocation loc : list.getRegionLocations()) {
          if (loc != null) {
            locations.add(loc);
          }
        }
      }

The fix in my patch is to make it call locateRegion() only for a primary region.

Sub-Tasks

• Backport HBASE-20229 "ConnectionImplementation.locateRegions() returns duplicated entries when region replication is on" to branch-1: Resolved