Not really. In practice I write everything out to HDFS and that is
working fine. But I write lots of unit tests and example scripts and it
is convenient to be able to test a Spark application (or sequence of
spark functions) in a very local way such that it doesn't depend on any
outside infrastructure (e.g. an HDFS server.) So, it is convenient to
write out a small amount of data locally and manually inspect the
results - esp. as I'm building up a unit or regression test.
So, ultimately writing results out to a local file isn't that important
to me. However, I was just trying to run a simple example script that
worked before and is now not working.
Thanks,
Philip
On 1/2/2014 10:28 AM, Andrew Ash wrote:
You want to write it to a local file on the machine? Try using
"file:///path/to/target/mydir/" instead
I'm not sure what behavior would be if you did this on a multi-machine
cluster though -- you may get a bit of data on each machine in that
local directory.
On Thu, Jan 2, 2014 at 12:22 PM, Philip Ogren <[email protected]
<mailto:[email protected]>> wrote:
I have a very simple Spark application that looks like the following:
var myRdd: RDD[Array[String]] = initMyRdd()
println(myRdd.first.mkString(", "))
println(myRdd.count)
myRdd.saveAsTextFile("hdfs://myserver:8020/mydir")
myRdd.saveAsTextFile("target/mydir/")
The println statements work as expected. The first saveAsTextFile
statement also works as expected. The second saveAsTextFile
statement does not (even if the first is commented out.) I get
the exception pasted below. If I inspect "target/mydir" I see
that there is a directory called
_temporary/0/_temporary/attempt_201401020953_0000_m_000000_1 which
contains an empty part-00000 file. It's curious because this code
worked before with Spark 0.8.0 and now I am running on Spark
0.8.1. I happen to be running this on Windows in "local" mode at
the moment. Perhaps I should try running it on my linux box.
Thanks,
Philip
Exception in thread "main" org.apache.spark.SparkException: Job
aborted: Task 2.0:0 failed more than 0 times; aborting job
java.lang.NullPointerException
at
org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:827)
at
org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:825)
at
scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:60)
at
scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:47)
at
org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:825)
at
org.apache.spark.scheduler.DAGScheduler.processEvent(DAGScheduler.scala:440)
at org.apache.spark.scheduler.DAGScheduler.org
<http://org.apache.spark.scheduler.DAGScheduler.org>$apache$spark$scheduler$DAGScheduler$$run(DAGScheduler.scala:502)
at
org.apache.spark.scheduler.DAGScheduler$$anon$1.run(DAGScheduler.scala:157)
