Engineering Questions with Answers - Multiple Choice Questions
MCQs on MapReduce Job – 2
1 - Question
_________ is a data migration tool added for archiving data.
a) Mover
b) Hiver
c) Serde
d) None of the mentioned
View Answer
Answer: a
Explanation: Mover periodically scans the files in HDFS to check if the block placement satisfies the storage policy.
2 - Question
Point out the correct statement.
a) Mover is not similar to Balancer
b) hdfs dfsadmin -setStoragePolicy <path> <policyName> puts a storage policy to a file or a directory.
c) addCacheArchive add archives to be localized
d) none of the mentioned
View Answer
Answer: c
Explanation: addArchiveToClassPath(Path archive) adds an archive path to the current set of classpath entries.
3 - Question
Which of the following is used to list out the storage policies?
a) hdfs storagepolicies
b) hdfs storage
c) hd storagepolicies
d) all of the mentioned
View Answer
Answer: a
Explanation: Arguments are none for the hdfs storagepolicies command.
4 - Question
Which of the following statement can be used to get the storage policy of a file or a directory?
a) hdfs dfsadmin -getStoragePolicy path
b) hdfs dfsadmin -setStoragePolicy path policyName
c) hdfs dfsadmin -listStoragePolicy path policyName
d) all of the mentioned
View Answer
Answer: a
Explanation: refers to the path referring to either a directory or a file.
5 - Question
Point out the wrong statement.
a) getInstance() creates a new Job with particular cluster
b) getInstance(Configuration conf) creates a new Job with no particular Cluster and a given Configuration
c) getInstance(JobStatus status, Configuration conf) creates a new Job with no particular Cluster and given Configuration and JobStatus
d) all of the mentioned
View Answer
Answer: a
Explanation: getInstance() creates a new Job with particular cluster.
6 - Question
Which of the following method is used to get user-specified job name?
a) getJobName()
b) getJobState()
c) getPriority()
d) all of the mentioned
View Answer
Answer: a
Explanation: getPriority() is used to get scheduling info of the job.
7 - Question
__________ get events indicating completion (success/failure) of component tasks.
a) getJobName()
b) getJobState()
c) getPriority()
d) getTaskCompletionEvents(int startFrom)
View Answer
Answer: d
Explanation: getPriority() provides scheduling info of the job.
8 - Question
_________ gets the diagnostic messages for a given task attempt.
a) getTaskOutputFilter(Configuration conf)
b) getTaskReports(TaskType type)
c) getTrackingURL()
d) all of the mentioned
View Answer
Answer: a
Explanation: getTaskDiagnostics(TaskAttemptID taskid) gets the diagnostic messages for a given task attempt.
9 - Question
reduceProgress() gets the progress of the job’s reduce-tasks, as a float between _________
a) 0.0-1.0
b) 1.0-2.0
c) 2.0-3.0
d) None of the mentioned
View Answer
Answer: a
Explanation: mapProgress() is used to get the progress of the job’s map-tasks, as a float between 0.0 and 1.0.
10 - Question
The Job makes a copy of the _____________ so that any necessary internal modifications do not reflect on the incoming parameter.
a) Component
b) Configuration
c) Collector
d) None of the mentioned
View Answer
Answer: b
Explanation: A Cluster will be created from the conf parameter only when it’s needed.