Hi Jacin,
If I was you, first thing that I would do is, write a sample java
application to write data into hdfs and see if it's working fine. Meta data
is being created in hdfs, that means, communication to namenode is working
fine but not to datanodes since you don't see any data inside the file. Why
don't you see hdfs logs and see what's happening when your application is
talking to namenode? I suspect some networking issue or check if the
datanodes are running fine.
Thank you,
Ajay
On Saturday, October 3, 2015, Jacinto Arias <ja...@elrocin.es> wrote:
> Yes printing the result with collect or take is working,
>
> actually this is a minimal example, but also when working with real data
> the actions are performed, and the resulting RDDs can be printed out
> without problem. The data is there and the operations are correct, they
> just cannot be written to a file.
>
>
> On 03 Oct 2015, at 16:17, Ted Yu <yuzhih...@gmail.com
> <javascript:_e(%7B%7D,'cvml','yuzhih...@gmail.com');>> wrote:
>
> bq. val dist = sc.parallelize(l)
>
> Following the above, can you call, e.g. count() on dist before saving ?
>
> Cheers
>
> On Fri, Oct 2, 2015 at 1:21 AM, jarias <ja...@elrocin.es
> <javascript:_e(%7B%7D,'cvml','ja...@elrocin.es');>> wrote:
>
>> Dear list,
>>
>> I'm experimenting a problem when trying to write any RDD to HDFS. I've
>> tried
>> with minimal examples, scala programs and pyspark programs both in local
>> and
>> cluster modes and as standalone applications or shells.
>>
>> My problem is that when invoking the write command, a task is executed but
>> it just creates an empty folder in the given HDFS path. I'm lost at this
>> point because there is no sign of error or warning in the spark logs.
>>
>> I'm running a seven node cluster managed by cdh5.7, spark 1.3. HDFS is
>> working properly when using the command tools or running MapReduce jobs.
>>
>>
>> Thank you for your time, I'm not sure if this is just a rookie mistake or
>> an
>> overall config problem.
>>
>> Just a working example:
>>
>> This sequence produces the following log and creates the empty folder
>> "test":
>>
>> scala> val l = Seq.fill(10000)(nextInt)
>> scala> val dist = sc.parallelize(l)
>> scala> dist.saveAsTextFile("hdfs://node1.i3a.info/user/jarias/test/")
>>
>>
>> 15/10/02 10:19:22 INFO FileOutputCommitter: File Output Committer
>> Algorithm
>> version is 1
>> 15/10/02 10:19:22 INFO SparkContext: Starting job: saveAsTextFile at
>> <console>:27
>> 15/10/02 10:19:22 INFO DAGScheduler: Got job 3 (saveAsTextFile at
>> <console>:27) with 2 output partitions (allowLocal=false)
>> 15/10/02 10:19:22 INFO DAGScheduler: Final stage: Stage 3(saveAsTextFile
>> at
>> <console>:27)
>> 15/10/02 10:19:22 INFO DAGScheduler: Parents of final stage: List()
>> 15/10/02 10:19:22 INFO DAGScheduler: Missing parents: List()
>> 15/10/02 10:19:22 INFO DAGScheduler: Submitting Stage 3
>> (MapPartitionsRDD[7]
>> at saveAsTextFile at <console>:27), which has no missing parents
>> 15/10/02 10:19:22 INFO MemoryStore: ensureFreeSpace(137336) called with
>> curMem=184615, maxMem=278302556
>> 15/10/02 10:19:22 INFO MemoryStore: Block broadcast_3 stored as values in
>> memory (estimated size 134.1 KB, free 265.1 MB)
>> 15/10/02 10:19:22 INFO MemoryStore: ensureFreeSpace(47711) called with
>> curMem=321951, maxMem=278302556
>> 15/10/02 10:19:22 INFO MemoryStore: Block broadcast_3_piece0 stored as
>> bytes
>> in memory (estimated size 46.6 KB, free 265.1 MB)
>> 15/10/02 10:19:22 INFO BlockManagerInfo: Added broadcast_3_piece0 in
>> memory
>> on nodo1.i3a.info:36330 (size: 46.6 KB, free: 265.3 MB)
>> 15/10/02 10:19:22 INFO BlockManagerMaster: Updated info of block
>> broadcast_3_piece0
>> 15/10/02 10:19:22 INFO SparkContext: Created broadcast 3 from broadcast at
>> DAGScheduler.scala:839
>> 15/10/02 10:19:22 INFO DAGScheduler: Submitting 2 missing tasks from
>> Stage 3
>> (MapPartitionsRDD[7] at saveAsTextFile at <console>:27)
>> 15/10/02 10:19:22 INFO YarnScheduler: Adding task set 3.0 with 2 tasks
>> 15/10/02 10:19:22 INFO TaskSetManager: Starting task 0.0 in stage 3.0 (TID
>> 6, nodo2.i3a.info, PROCESS_LOCAL, 25975 bytes)
>> 15/10/02 10:19:22 INFO TaskSetManager: Starting task 1.0 in stage 3.0 (TID
>> 7, nodo3.i3a.info, PROCESS_LOCAL, 25963 bytes)
>> 15/10/02 10:19:22 INFO BlockManagerInfo: Added broadcast_3_piece0 in
>> memory
>> on nodo2.i3a.info:37759 (size: 46.6 KB, free: 530.2 MB)
>> 15/10/02 10:19:22 INFO BlockManagerInfo: Added broadcast_3_piece0 in
>> memory
>> on nodo3.i3a.info:54798 (size: 46.6 KB, free: 530.2 MB)
>> 15/10/02 10:19:22 INFO TaskSetManager: Finished task 0.0 in stage 3.0 (TID
>> 6) in 312 ms on nodo2.i3a.info (1/2)
>> 15/10/02 10:19:23 INFO TaskSetManager: Finished task 1.0 in stage 3.0 (TID
>> 7) in 313 ms on nodo3.i3a.info (2/2)
>> 15/10/02 10:19:23 INFO YarnScheduler: Removed TaskSet 3.0, whose tasks
>> have
>> all completed, from pool
>> 15/10/02 10:19:23 INFO DAGScheduler: Stage 3 (saveAsTextFile at
>> <console>:27) finished in 0.334 s
>> 15/10/02 10:19:23 INFO DAGScheduler: Job 3 finished: saveAsTextFile at
>> <console>:27, took 0.436388 s
>>
>>
>>
>>
>> --
>> View this message in context:
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>> Sent from the Apache Spark User List mailing list archive at Nabble.com.
>>
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