Suspicious numbers in Spout tuples emitted, failed, acked v/s max.pending tuples

[Girish Reddy <gi...@gmail.com>]

Hello,

I'm using storm-0.9.6 and have a topology with KafkaSpout and 3 other
bolts. I've max.spout.pending : 500, message.timeout : 30, acker.executors:
10.

I see the following numbers for kafka-spout in UI :

*Executors Tasks Emitted Transferred Acked Failed*
*3* *3* *834380* *834380* *414420* *0*

My question here is why do I see a huge difference between emitted and
acked + failed (834380 - 414420 = 419960) when I set the max.spout.pending
as 500. Does that mean there are still 419960 tuples in flight? Or does it
mean they still need to be acked? I'm asking this because I want to
understand if my spout processed all the tuples and once I'm done I want to
kick off some action like for example killing topology/sending email or
whatever. Or to be precise, I want to understand if there are any tuples in
flight.

I'm forming tuple tree by anchoring tuples and ultimately acking/failing
the tuple tree at the sink bolt.

Please help!

Thanks,
Girish.