> #1 when a worker is died or killed by manually, storm framework will restart > this worker, is there a ID which doesn't change for the new worker and the > died worker? if there is, how to get it?
Task Id does not change. The worker can be restarted in the same or different host and the tasks would be reassigned. > #2 when a worker is died, is there a case storm framework can't start a new > worker? In this case, how about the grouped message handled by this worker, > it will auto take over by other workers? As long as the state is per task it can be handled by other worker. > #3 suppose we have started a topology with 3 workers, rebalance topology can > change the worker numbers? Rebalance can change the number of workers, but the overall number of tasks remains the same. Only that the task assignment to workers could change. Not sure if you are building something different, but storm already has basic support for stateful bolts (see https://github.com/apache/storm/blob/master/docs/State-checkpointing.md). Thanks, Arun From: "shawn.du" <shawn...@neulion.com.cn> Reply-To: "user@storm.apache.org" <user@storm.apache.org> Date: Tuesday, February 7, 2017 at 11:25 AM To: user <user@storm.apache.org> Subject: implmement state management with Apache Ignite Hi community, Recently we are trying implement state management using apache ignite. Before do the real work, I have several questions, please help. #1 when a worker is died or killed by manually, storm framework will restart this worker, is there a ID which doesn't change for the new worker and the died worker? if there is, how to get it? #2 when a worker is died, is there a case storm framework can't start a new worker? In this case, how about the grouped message handled by this worker, it will auto take over by other workers? #3 suppose we have started a topology with 3 workers, rebalance topology can change the worker numbers? Thanks Shawn