[HDDS-2591] No tailMap needed for startIndex 0 in ContainerSet#listContainer

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 0.5.0
• Component/s: Ozone Datanode
• Labels: pull-request-available
• Target Version/s: 0.5.0
• Assignee: Attila Doroszlai
• Reporter: Attila Doroszlai
• Created: 20/Nov/19 20:05
• Updated: 24/Feb/20 20:56
• Resolved: 22/Nov/19 22:24

Description

ContainerSet#listContainer has this code:

https://github.com/apache/hadoop-ozone/blob/3c334f6a7b344e0e5f52fec95071c369286cfdcb/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/impl/ContainerSet.java#L198

map = containerMap.tailMap(containerMap.firstKey(), true);

This is equivalent to:

map = containerMap;

since tailMap is a sub-map with all keys larger than or equal to (inclusive=true) firstKey, which is the lowest key in the map. So it is a sub-map with all keys, ie. the whole map.

Issue Links

• links to: GitHub Pull Request #254