@Matthew: That's the exact same article I've linked to in my first post (on the word "explanation"). I couldn't understand it, which is why I asked here. Funny thing is, this answer on Stackoverflow <http://stackoverflow.com/questions/27964271/storm-dynamically-increasing-the-executors> explains tasks like as though they are the BoltParallelism (from my code), but when I set BoltParallelism, I noticed that there were 3 instances of BoltA created even though I did not specify any setNumTasks.
On Mon, May 16, 2016 at 1:18 PM, Matthew Lowe <[email protected]> wrote: > 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 >> <http://www.michael-noll.com/blog/2012/10/16/understanding-the-parallelism-of-a-storm-topology/>, >> 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 >> > > -- Regards, Navin
