AH!!! Got it! Should I use 2.0.1 then ? I don't see 2.1.0 On Tue, Nov 1, 2016 at 10:14 AM, Shixiong(Ryan) Zhu <shixi...@databricks.com > wrote:
> Dstream "Window" uses "union" to combine multiple RDDs in one window into > a single RDD. > > On Tue, Nov 1, 2016 at 2:59 AM kant kodali <kanth...@gmail.com> wrote: > >> @Sean It looks like this problem can happen with other RDD's as well. Not >> just unionRDD >> >> On Tue, Nov 1, 2016 at 2:52 AM, kant kodali <kanth...@gmail.com> wrote: >> >> Hi Sean, >> >> The comments seem very relevant although I am not sure if this pull >> request https://github.com/apache/spark/pull/14985 would fix my issue? I >> am not sure what unionRDD.scala has anything to do with my error (I don't >> know much about spark code base). Do I ever use unionRDD.scala when I call >> mapToPair or ReduceByKey or forEachRDD? This error is very easy to >> reproduce you actually don't need to ingest any data to spark streaming >> job. Just have one simple transformation consists of mapToPair, reduceByKey >> and forEachRDD and have the window interval of 1min and batch interval of >> one one second and simple call ssc.awaitTermination() and watch the >> Thread Count go up significantly. >> >> I do think that using a fixed size executor service would probably be a >> safer approach. One could leverage ForJoinPool if they think they could >> benefit a lot from the work-steal algorithm and doubly ended queues in the >> ForkJoinPool. >> >> Thanks! >> >> >> >> >> On Tue, Nov 1, 2016 at 2:19 AM, Sean Owen <so...@cloudera.com> wrote: >> >> Possibly https://issues.apache.org/jira/browse/SPARK-17396 ? >> >> On Tue, Nov 1, 2016 at 2:11 AM kant kodali <kanth...@gmail.com> wrote: >> >> Hi Ryan, >> >> I think you are right. This may not be related to the Receiver. I have >> attached jstack dump here. I do a simple MapToPair and reduceByKey and I >> have a window Interval of 1 minute (60000ms) and batch interval of 1s ( >> 1000) This is generating lot of threads atleast 5 to 8 threads per >> second and the total number of threads is monotonically increasing. So just >> for tweaking purpose I changed my window interval to 1min (60000ms) and >> batch interval of 10s (10000) this looked lot better but still not ideal >> at very least it is not monotonic anymore (It goes up and down). Now my >> question really is how do I tune such that my number of threads are >> optimal while satisfying the window Interval of 1 minute (60000ms) and >> batch interval of 1s (1000) ? >> >> This jstack dump is taken after running my spark driver program for 2 >> mins and there are about 1000 threads. >> >> Thanks! >> >> >> >>
