Apache-Hadoop-Developer 試験問題を無料オンラインアクセス

A NameNode in Hadoop 2.0 manages ______________.

• A.An arbitrary number of namespaces
• B.Two namespaces: an active namespace and a backup namespace
• C.A single namespace
• D.No namespaces

What is the term for the process of moving map outputs to the reducers?

• A.Combining
• B.Partitioning
• C.Shuffling and sorting
• D.Reducing

You have just executed a MapReduce job. Where is intermediate data written to after being emitted from the Mapper's map method?

• A.Into in-memory buffers on the TaskTracker node running the Reducer that spill over and are written into HDFS.
• B.Into in-memory buffers that spill over to the local file system of the TaskTracker node running the Mapper.
• C.Intermediate data in streamed across the network from Mapper to the Reduce and is never written to disk.
• D.Into in-memory buffers on the TaskTracker node running the Mapper that spill over and are written into HDFS.
• E.Into in-memory buffers that spill over to the local file system (outside HDFS) of the TaskTracker node running the Reducer

To process input key-value pairs, your mapper needs to lead a 512 MB data file in memory. What is the best way to accomplish this?

• A.Place the data file in the DistributedCache and read the data into memory in the configure method of the mapper.
• B.Place the data file in the DataCache and read the data into memory in the configure method of the mapper.
• C.Place the data file in the DistributedCache and read the data into memory in the map method of the mapper.
• D.Serialize the data file, insert in it the JobConf object, and read the data into memory in the configure method of the mapper.

Which two of the following are true about this trivial Pig program' (choose Two)

• A.ABC has a schema associated with it
• B.Pig assumes the contents of myfile are comma delimited
• C.myfile is read from the user's home directory in HDFS
• D.The contents of myfile appear on stdout