Nick Pritchard created SPARK-10942:
--------------------------------------

             Summary: Not all cached RDDs are unpersisted
                 Key: SPARK-10942
                 URL: https://issues.apache.org/jira/browse/SPARK-10942
             Project: Spark
          Issue Type: Bug
          Components: Streaming
            Reporter: Nick Pritchard


I have a Spark Streaming application that caches RDDs inside of a {{transform}} 
closure. Looking at the Spark UI, it seems that most of these RDDs are 
unpersisted after the batch completes, but not all.

I have copied a minimal reproducible example below to highlight the problem. I 
run this and monitor the Spark UI "Storage" tab. The example generates and 
caches 30 RDDs, and I see most get cleaned up. However in the end, some still 
remain cached. There is some randomness going on because I see different RDDs 
remain cached for each run.

I have marked this as Major because I haven't been able to workaround it and it 
is a memory leak for my application. I tried setting {{spark.cleaner.ttl}} but 
that did not change anything.

{code}
val inputRDDs = mutable.Queue.tabulate(30) { i =>
  sc.parallelize(Seq(i))
}
val input: DStream[Int] = ssc.queueStream(inputRDDs)

val output = input.transform { rdd =>
  if (rdd.isEmpty()) {
    rdd
  } else {
    val rdd2 = rdd.map(identity)
    rdd2.setName(rdd.first().toString)
    rdd2.cache()
    val rdd3 = rdd2.map(identity)
    rdd3
  }
}
output.print()

ssc.start()
ssc.awaitTermination()
{code}



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org

Reply via email to