Both. topology.max.spout.pending specifies how many batches are processed in parallel. However, for state updates, the batches are processed sequentially. So the state update for batch 2 won't be executed until the state update for batch 1 succeeds.
On Tue, May 13, 2014 at 10:31 AM, Raphael Hsieh <[email protected]>wrote: > In Storm Trident are batches processed sequentially? Or are they all > processed in parallel? > If they are processed in parallel how does it handle multiple writers to a > datastore ? > > I can understand this making sense for append-only implementations, but > for cases where we are updating values in a database, how does it make sure > that values are written, and in the database before another thread reads it > and tries to update it with different data? > > Thanks > -- > Raphael Hsieh > > > > -- Twitter: @nathanmarz http://nathanmarz.com
