I think this is a great article to read: http://www.michael-noll.com/blog/2012/10/16/understanding-the-parallelism-of-a-storm-topology/
Best Regards Matthew Lowe > On 16 May 2016, at 09:07, Adrien Carreira <[email protected]> wrote: > > +1 > > 2016-05-16 6:40 GMT+02:00 Navin Ipe <[email protected]>: >> Hi, >> >> I've seen the explanations, but none of them explain it in terms of what I >> see in the code. This is what I understood: >> >> int BoltParallelism = 3; >> int BoltTaskParallelism = 2; >> builder.setBolt("bolt1", new BoltA(), BoltParallelism) >> .setNumTasks(BoltTaskParallelism) >> >> BoltParallelism creates 3 instances of BoltA. These are the executors. >> BoltTaskParallelism allows Tuples to come into BoltA very fast, and the Bolt >> creates a task for processing each incoming Tuple. If there are not enough >> tasks, then the excess Tuples are made to wait in a queue of the executor. >> >> Strange thing is that the explanation says the tasks are run in a single >> thread, so obviously I misunderstood something. Could you help me understand >> it? >> >> -- >> Regards, >> Navin >
