Hi Ted, all,

do you have any advice regarding my questions in my initial email?

I tried Spark 1.5.2 and 1.6.0 without success. The problem seems to be that RDDs use some transient fields which are not restored when they are recovered from checkpoint files. In case of some RDD implementations it is SparkContext, but it can be also implementation specific Configuration object, etc. I see in the sources that in the case of DStream recovery, the DStreamGraph takes care of restoring StreamingContext in all its DStream-s. But I haven't found any similar mechanism for RDDs.

So my question is whether I am doing something wrong or this is a bug in Spark? If later, is there some workaround except for implementing a custom DStream which will return the same RDD every batch interval and joining at DStream level instead of RDD level in transform?

Thanks,
Lubo

On 18.3.2016 18:36, Ted Yu wrote:
This is the line where NPE came from:

    if (conf.get(SCAN) != null) {

So Configuration instance was null.

On Fri, Mar 18, 2016 at 9:58 AM, Lubomir Nerad <lubomir.ne...@oracle.com <mailto:lubomir.ne...@oracle.com>> wrote:

    The HBase version is 1.0.1.1.

    Thanks,
    Lubo


    On 18.3.2016 17:29, Ted Yu wrote:
    I looked at the places in SparkContext.scala where NewHadoopRDD
    is constrcuted.
    It seems the Configuration object shouldn't be null.

    Which hbase release are you using (so that I can see which line
    the NPE came from) ?

    Thanks

    On Fri, Mar 18, 2016 at 8:05 AM, Lubomir Nerad
    <lubomir.ne...@oracle.com <mailto:lubomir.ne...@oracle.com>> wrote:

        Hi,

        I tried to replicate the example of joining DStream with
        lookup RDD from
        
http://spark.apache.org/docs/latest/streaming-programming-guide.html#transform-operation.
        It works fine, but when I enable checkpointing for the
        StreamingContext and let the application to recover from a
        previously created checkpoint, I always get an exception
        during start and the whole application fails. I tried various
        types of lookup RDD, but the result is the same.

        Exception in the case of HBase RDD is:

        Exception in thread "main" java.lang.NullPointerException
            at
        
org.apache.hadoop.hbase.mapreduce.TableInputFormat.setConf(TableInputFormat.java:119)
            at
        org.apache.spark.rdd.NewHadoopRDD.getPartitions(NewHadoopRDD.scala:109)
            at
        org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:239)
            at
        org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:237)
            at scala.Option.getOrElse(Option.scala:120)
            at org.apache.spark.rdd.RDD.partitions(RDD.scala:237)
            at
        
org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35)
            at
        org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:239)
            at
        org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:237)
            at scala.Option.getOrElse(Option.scala:120)
            at org.apache.spark.rdd.RDD.partitions(RDD.scala:237)
            at
        
org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35)
            at
        org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:239)
            at
        org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:237)
            at scala.Option.getOrElse(Option.scala:120)
            at org.apache.spark.rdd.RDD.partitions(RDD.scala:237)
            at
        org.apache.spark.Partitioner$$anonfun$2.apply(Partitioner.scala:58)
            at
        org.apache.spark.Partitioner$$anonfun$2.apply(Partitioner.scala:58)
            at scala.math.Ordering$$anon$5.compare(Ordering.scala:122)
            at
        java.util.TimSort.countRunAndMakeAscending(TimSort.java:351)
            at java.util.TimSort.sort(TimSort.java:216)
            at java.util.Arrays.sort(Arrays.java:1438)
            at scala.collection.SeqLike$class.sorted(SeqLike.scala:615)
            at scala.collection.AbstractSeq.sorted(Seq.scala:40)
            at scala.collection.SeqLike$class.sortBy(SeqLike.scala:594)
            at scala.collection.AbstractSeq.sortBy(Seq.scala:40)
            at
        org.apache.spark.Partitioner$.defaultPartitioner(Partitioner.scala:58)
            at
        
org.apache.spark.rdd.PairRDDFunctions$$anonfun$join$2.apply(PairRDDFunctions.scala:651)
            at
        
org.apache.spark.rdd.PairRDDFunctions$$anonfun$join$2.apply(PairRDDFunctions.scala:651)
            at
        
org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:150)
            at
        
org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:111)
            at org.apache.spark.rdd.RDD.withScope(RDD.scala:316)
            at
        org.apache.spark.rdd.PairRDDFunctions.join(PairRDDFunctions.scala:650)
            at
        org.apache.spark.api.java.JavaPairRDD.join(JavaPairRDD.scala:546)

        I tried Spark 1.5.2 and 1.6.0 without success. The problem
        seems to be that RDDs use some transient fields which are not
        restored when they are recovered from checkpoint files. In
        case of some RDD implementations it is SparkContext, but it
        can be also implementation specific Configuration object,
        etc. I see in the sources that in the case of DStream
        recovery, the DStreamGraph takes care of restoring
        StreamingContext in all its DStream-s. But I haven't found
        any similar mechanism for RDDs.

        So my question is whether I am doing something wrong or this
        is a bug in Spark? If later, is there some workaround except
        for implementing a custom DStream which will return the same
        RDD every batch interval and joining at DStream level instead
        of RDD level in transform?

        I apologize if this has been discussed in the past and I
        missed it when looking into archive.

        Thanks,
        Lubo


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