[STORM-3222] Fix KafkaSpout internals to use LinkedList instead of ArrayList

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.0, 1.2.2
• Fix Version/s: 2.0.0, 1.2.3, 1.1.4
• Labels: pull-request-available
• Assignee: Arun Mahadevan
• Reporter: Arun Mahadevan
• Created: 12/Sep/18 22:35
• Updated: 16/Sep/18 11:07
• Resolved: 14/Sep/18 18:10

Description

KafkaSpout internally maintains a waitingToEmit list per topic partition and keeps removing the first item to emit during each nextTuple. The implementation uses an ArrayList which results in un-necessary traversal and copy for each tuple.

Also I am not sure why the nextTuple only emits a single tuple wheres ideally it should emit whatever it can emit in a single nextTuple call which is more efficient. However the logic appears too complicated to refactor.

Issue Links

• links to: GitHub Pull Request #2829
• links to: GitHub Pull Request #2835