Hi,
I'm a newbie of Storm. I'm using it for an University project. I hope that
writing an email is the correct way to receive support (I read that the
Google group is now deprecated).
I created my topology, with a Spout linked to a MySql database, and two
Bolts. The first bolt, linked to the spout, prepares and removes
information not necessary of the tuples; the second, do a filtering of the
tuple.
I'm working in local mode.
My question is:
why after running topology, in my console I see output like the lines below?
38211 [Thread-14-movie-SPOUT] INFO backtype.storm.daemon.executor -
> Processing received message source: __system:-1, stream: __tick, id: {},
> [30]
> 67846 [Thread-10-__acker] INFO backtype.storm.daemon.executor -
> Processing received message source: __system:-1, stream: __metrics_tick,
> id: {}, [60]
> 67846 [Thread-8-cleaning-genre-bolt] INFO backtype.storm.daemon.executor
> - Processing received message source: __system:-1, stream: __metrics_tick,
> id: {}, [60]
> 67852 [Thread-10-__acker] INFO backtype.storm.daemon.task - Emitting:
> __acker __metrics [#<TaskInfo backtype.storm.metric.api.
> IMetricsConsumer$TaskInfo@3c270095> [#<DataPoint [__emit-count = {}]>
> #<DataPoint [__process-latency = {}]> #<DataPoint [__receive = {read_pos=0,
> write_pos=1, capacity=1024, population=1}]> #<DataPoint [__ack-count = {}]>
> #<DataPoint [__transfer-count = {}]> #<DataPoint [__execute-latency = {}]>
> #<DataPoint [__fail-count = {}]> #<DataPoint [__sendqueue = {read_pos=-1,
> write_pos=-1, capacity=1024, population=0}]> #<DataPoint [__execute-count =
> {}]>]]
> 67853 [Thread-8-cleaning-genre-bolt] INFO backtype.storm.daemon.task -
> Emitting: cleaning-genre-bolt __metrics [#<TaskInfo
> backtype.storm.metric.api.IMetricsConsumer$TaskInfo@38c3d111>
> [#<DataPoint [__emit-count = {default=1680}]> #<DataPoint
> [__process-latency = {}]> #<DataPoint [__receive = {read_pos=1621,
> write_pos=1622, capacity=1024, population=1}]> #<DataPoint [__ack-count =
> {}]> #<DataPoint [__transfer-count = {default=1680}]> #<DataPoint
> [__execute-latency = {movie-SPOUT:default=0.15476190476190477}]>
> #<DataPoint [__fail-count = {}]> #<DataPoint [__sendqueue = {read_pos=1680,
> write_pos=1680, capacity=1024, population=0}]> #<DataPoint [__execute-count
> = {movie-SPOUT:default=1680}]>]]
> 67854 [Thread-13-filtering-genre-BOLT] INFO
> backtype.storm.daemon.executor - Processing received message source:
> __system:-1, stream: __metrics_tick, id: {}, [60]
> 67855 [Thread-13-filtering-genre-BOLT] INFO backtype.storm.daemon.task -
> Emitting: filtering-genre-BOLT __metrics [#<TaskInfo
> backtype.storm.metric.api.IMetricsConsumer$TaskInfo@6d5c75a9>
> [#<DataPoint [__emit-count = {}]> #<DataPoint [__process-latency = {}]>
> #<DataPoint [__receive = {read_pos=1681, write_pos=1682, capacity=1024,
> population=1}]> #<DataPoint [__ack-count = {}]> #<DataPoint
> [__transfer-count = {}]> #<DataPoint [__execute-latency =
> {cleaning-genre-bolt:default=0.08333333333333333}]> #<DataPoint
> [__fail-count = {}]> #<DataPoint [__sendqueue = {read_pos=-1, write_pos=-1,
> capacity=1024, population=0}]> #<DataPoint [__execute-count =
> {cleaning-genre-bolt:default=1680}]>]]
>
I read that these lines after the last tuple processed are to be considered
normal. Isn't it?
And how can I run other code after the submission of topology? For example,
I want to print the results of my filtering done in the second bolt, saved
in a HashMap.
If I put my code after the line containing the submitTopology() method, the
code is ran before the completion of the tuples.
The second and last question is: why in every example of Storm, I see in
the Spout
> "Thread.sleep(1000)"?
>
I hope my questions are clear.
Thank you in advance!
Mario Ferrulli
