I'm trying to build a trident topology that grabs data from an external
source and collects statistics on sessions. The documentation on Trident
seems to be a bit sparse, though, so I'm hoping someone can answer a few
- Is it okay for spouts and bolts to perform blocking operations in their
emitPartitionBatch and execute methods?
- Does Trident persist state instances in any way? The memory state, for
instance, has transactional and opaque transactional variants, but without
some sort of persistence to disk, this isn't going to be resilient to
machine failure. Does Trident take care of this, or is it a state class's
- I need a map state that expires entries after a fixed period. Can anyone
suggest a way to do this - preferably by building something on top of
existing state classes?
- Are there any plans to release a new version of Storm to take care of the
issue with new versions of zookeeper, which is fixed in SVN?