MapReduce job tuning parameters in Hadoop - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the number of reduce tasks in a MapReduce job.

Hadoop

job.setNumReduceTasks([1]);

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AreduceTasks

B5

C10

Dmapreduce.job.reduces

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string property name instead of an integer.

Confusing map tasks with reduce tasks.

The method setNumReduceTasks takes an integer to specify how many reduce tasks to run.

2fill in blank

medium

Complete the code to set the memory allocated for map tasks in megabytes.

Hadoop

conf.setInt("mapreduce.map.memory.mb", [1]);

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A"2048"

B2GB

C2048

DmemoryMap

Attempts:

3 left

💡 Hint

Common Mistakes

Passing memory size as a string instead of integer.

Using units like '2GB' instead of megabytes.

The setInt method expects an integer value for memory in MB, so 2048 is correct.

3fill in blank

hard

Fix the error in setting the speculative execution for reduce tasks.

Hadoop

conf.setBoolean("mapreduce.reduce.speculative", [1]);

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Atrue

B"true"

C1

Denabled

Attempts:

3 left

💡 Hint

Common Mistakes

Passing 'true' as a string instead of boolean.

Using 1 or 0 instead of true or false.

The setBoolean method requires a boolean value true or false, not a string or number.

4fill in blank

hard

Fill both blanks to configure the input split size and the maximum split size.

Hadoop

conf.setLong("mapreduce.input.fileinputformat.split.minsize", [1]);
conf.setLong("mapreduce.input.fileinputformat.split.maxsize", [2]);

Drag options to blanks, or click blank then click option'

A134217728

B268435456

CsplitSize

DmaxSplit

Attempts:

3 left

💡 Hint

Common Mistakes

Using variable names instead of numeric byte values.

Confusing min and max split sizes.

The minimum split size is set to 128MB (134217728 bytes) and the maximum split size to 256MB (268435456 bytes).

5fill in blank

hard

Fill all three blanks to create a map output compression configuration.

Hadoop

conf.setBoolean("mapreduce.map.output.compress", [1]);
conf.set("mapreduce.map.output.compress.codec", [2]);
conf.setInt("mapreduce.task.io.sort.mb", [3]);

Drag options to blanks, or click blank then click option'

Atrue

B"org.apache.hadoop.io.compress.SnappyCodec"

C256

Dfalse

Attempts:

3 left

💡 Hint

Common Mistakes

Disabling compression by setting false.

Using incorrect codec class names.

Passing sort buffer size as string instead of integer.

Enable compression with true, set codec to Snappy, and allocate 256MB for sort buffer.