From 889f7b7624689444ecdb4f0ca16ef78f9bfc8430 Mon Sep 17 00:00:00 2001 From: Vadim Chekan Date: Tue, 17 Jun 2014 22:03:50 -0700 Subject: [STREAMING] SPARK-2009 Key not found exception when slow receiver starts I got "java.util.NoSuchElementException: key not found: 1401756085000 ms" exception when using kafka stream and 1 sec batchPeriod. Investigation showed that the reason is that ReceiverLauncher.startReceivers is asynchronous (started in a thread). https://github.com/vchekan/spark/blob/master/streaming/src/main/scala/org/apache/spark/streaming/scheduler/ReceiverTracker.scala#L206 In case of slow starting receiver, such as Kafka, it easily takes more than 2sec to start. In result, no single "compute" will be called on ReceiverInputDStream before first batch job is executed and receivedBlockInfo remains empty (obviously). Batch job will cause ReceiverInputDStream.getReceivedBlockInfo call and "key not found" exception. The patch makes getReceivedBlockInfo more robust by tolerating missing values. Author: Vadim Chekan Closes #961 from vchekan/branch-1.0 and squashes the following commits: e86f82b [Vadim Chekan] Fixed indentation 4609563 [Vadim Chekan] Key not found exception: if receiver is slow to start, it is possible that getReceivedBlockInfo will be called before compute has been called (cherry picked from commit 26f6b989312a9a48a27a23ecc68702bd14032e55) Signed-off-by: Patrick Wendell --- .../scala/org/apache/spark/streaming/dstream/ReceiverInputDStream.scala | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'streaming') diff --git a/streaming/src/main/scala/org/apache/spark/streaming/dstream/ReceiverInputDStream.scala b/streaming/src/main/scala/org/apache/spark/streaming/dstream/ReceiverInputDStream.scala index 75cabdbf8d..391e40924f 100644 --- a/streaming/src/main/scala/org/apache/spark/streaming/dstream/ReceiverInputDStream.scala +++ b/streaming/src/main/scala/org/apache/spark/streaming/dstream/ReceiverInputDStream.scala @@ -74,7 +74,7 @@ abstract class ReceiverInputDStream[T: ClassTag](@transient ssc_ : StreamingCont /** Get information on received blocks. */ private[streaming] def getReceivedBlockInfo(time: Time) = { - receivedBlockInfo(time) + receivedBlockInfo.get(time).getOrElse(Array.empty[ReceivedBlockInfo]) } /** -- cgit v1.2.3