Actually, the interesting part in hadoop files is the sequencefile format which allows to split the data in various blocks. Other files in HDFS are single-blocks. They do not scale

An ObjectFile cannot be naturally splitted.

Usually, in Hadoop when storing a sequence of elements instead of a sequence of key,value the trick is to store key,null

I don't know what's the most effective way to do that in scala/spark. Actually that would be a good thing to add it to RDD[U]

Guillaume



On Fri, Jan 3, 2014 at 7:10 PM, Andrew Ash <[email protected]> wrote:
saveAsHadoopFile and saveAsNewAPIHadoopFile are on PairRDDFunctions which uses some Scala magic to become available when you have an that's RDD[Key, Value]


I see. So if my data is of RDD[Value] type, I cannot use compression? Why does it have to be of RDD[Key, Value] in order to save it in hadoop?

Also, doesn't saveAsObjectFile("hdfs://...") save data in hadoop? This is confusing.

I'm only interested in saving data on s3 ("s3n://..."), does it matter if I use saveAsHadoopFile, or saveAsObjectFile?
 


--
eXenSa
Guillaume PITEL, Président
+33(0)6 25 48 86 80 / +33(0)9 70 44 67 53

eXenSa S.A.S.
41, rue Périer - 92120 Montrouge - FRANCE
Tel +33(0)1 84 16 36 77 / Fax +33(0)9 72 28 37 05

Reply via email to