I would suggest you to also look at your nimbus & supervisor logs at the same time too. They will help paint the full picture to you.
Nimbus not getting a hearbeat back from the worker can lead to shutdown of the port as it tries to shift the worker to another free slot. (Assuming there was no kill or rebalance issued that forced this on your topology). I have not seen a case where Netty will cause this, others can chime on that. Key things to consider: 1. Your topology continues to work after this. If it’s not, then there is an issue. 2. You do not ack the tuples until they are completely processed so when the task re-spawns your tuples are replayed again. http://storm.apache.org/documentation/Fault-tolerance.html http://storm.apache.org/documentation/FAQ.html From: Nick R. Katsipoulakis [mailto:[email protected]] Sent: Thursday, June 25, 2015 12:18 PM To: [email protected] Subject: When is a task considered dead? Hello, I have the problem that at some point in a running topology, one of the tasks running gets restarted by Storm. Under which circumstances can the previous happen? Can it happen because of Netty (input rate of tuples is higher than the process rate)? I do not understand why the previous is happening and it is not definitely problem in my code because I can not find any exceptions in the worker log files. Any ideas/hints? Thanks, Nick
