Trident internals
Every Trident flow is a Storm flow. The concept of executors and workers is exactly the same as Storm. Trident topology is nothing but a Storm bolt. Trident operations such as spouts, each, and aggregations are actually implemented in Storm bolt.
Trident turns your topology into a dataflow (acyclic directed) graph that it uses to assign operations to bolts and then to assign those bolts to workers. It's smart enough to optimize that assignment: it combines operations into bolts so that, as much as possible, tuples are handed off with simple method cause and it arranges bolts among workers so that, as much as possible, tuples are handed off to local executors.
The actual spout of a Trident topology is called the Master Batch Coordinator (MBC). All it does is emit a tuple describing itself as batch 1 and then a tuple describing itself as batch 2, and so forth. Also deciding when to emit those batches, retry them, and so on, is quite exciting, but Storm doesn't know anything...
