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質問 1：
Assume you have a file named foo.txt in your local directory. You issue the following three commands:
Hadoop fs -mkdir input
Hadoop fs -put foo.txt input/foo.txt
Hadoop fs -put foo.txt input
What happens when you issue that third command?
A. You get a error message telling you that foo.txt already exists. The file is not written to HDFS
B. The write succeeds, overwriting foo.txt in HDFS with no warning
C. You get a warning that foo.txt is being overwritten
D. The file is uploaded and stored as a plain named input
E. You get an error message telling you that foo.txt already exists, and asking you if you would like to overwrite
F. You get an error message telling you that input is not a directory
G. The write silently fails
正解：A
質問 2：
Your cluster's mapped-site.xml includes the following parameters
<name>mapreduce.map.memory.mb</name>
<value>4096<value/>
<name>mapreduce.reduce.memory,mb</name>
<value>8192</value>
And your cluster's yarn-site.xml includes the following parameters
<name>yarn.nodemanager/vmen-pmem-ratio</name>
<value>2.1</value>
What is the maximum amount of virtual memory allocated for each map before YARN will kill its Container?
A. 4 GB
B. 8.2 GB
C. 17.2 GB
D. 24.6 GB
正解：B
解説: (Pass4Test メンバーにのみ表示されます)
質問 3：
Your cluster is running MapReduce vserion 2 (MRv2) on YARN. Your ResourceManager is configured to use the FairScheduler. Now you want to configure your scheduler such that a new user on the cluster can submit jobs into their own queue application submission. Which configuration should you set?
A. You can specify new queue name when user submits a job and new queue can be created dynamically if the property yarn.scheduler.fair.allow-undecleared-pools = true
B. Yarn.scheduler.fair.user-as-default-queue = false and yarn.scheduler.fair.allowundeclared-people = true
C. You can specify new queue name when user submits a job and new queue can be created dynamically if yarn.scheduler.fair.user-as-default-queue = false
D. You can specify new queue name per application in allocation.fair.allow-undeclaredpeople = true automatically assigned to the application queue
正解：C
質問 4：
You observe that the number of spilled records from Map tasks far exceeds the number of map output records. Your child heap size is 1GB and your io.sort.mb value is set to 100 MB. How would you tune your io.sort.mb value to achieve maximum memory to disk I/O ratio?
A. Tune the io.sort.mb value until you observe that the number of spilled records equals (or is as close to equals) the number of map output records
B. Increase the io.sort.mb to 1GB
C. For 1GB child heap size an io.sort.mb of 128 MB will always maximize memory to disk I/O
D. Decrease the io.sort.mb value to 0
正解：A
Assume you have a file named foo.txt in your local directory. You issue the following three commands:
Hadoop fs -mkdir input
Hadoop fs -put foo.txt input/foo.txt
Hadoop fs -put foo.txt input
What happens when you issue that third command?
A. You get a error message telling you that foo.txt already exists. The file is not written to HDFS
B. The write succeeds, overwriting foo.txt in HDFS with no warning
C. You get a warning that foo.txt is being overwritten
D. The file is uploaded and stored as a plain named input
E. You get an error message telling you that foo.txt already exists, and asking you if you would like to overwrite
F. You get an error message telling you that input is not a directory
G. The write silently fails
正解：A
質問 2：
Your cluster's mapped-site.xml includes the following parameters
<name>mapreduce.map.memory.mb</name>
<value>4096<value/>
<name>mapreduce.reduce.memory,mb</name>
<value>8192</value>
And your cluster's yarn-site.xml includes the following parameters
<name>yarn.nodemanager/vmen-pmem-ratio</name>
<value>2.1</value>
What is the maximum amount of virtual memory allocated for each map before YARN will kill its Container?
A. 4 GB
B. 8.2 GB
C. 17.2 GB
D. 24.6 GB
正解：B
解説: (Pass4Test メンバーにのみ表示されます)
質問 3：
Your cluster is running MapReduce vserion 2 (MRv2) on YARN. Your ResourceManager is configured to use the FairScheduler. Now you want to configure your scheduler such that a new user on the cluster can submit jobs into their own queue application submission. Which configuration should you set?
A. You can specify new queue name when user submits a job and new queue can be created dynamically if the property yarn.scheduler.fair.allow-undecleared-pools = true
B. Yarn.scheduler.fair.user-as-default-queue = false and yarn.scheduler.fair.allowundeclared-people = true
C. You can specify new queue name when user submits a job and new queue can be created dynamically if yarn.scheduler.fair.user-as-default-queue = false
D. You can specify new queue name per application in allocation.fair.allow-undeclaredpeople = true automatically assigned to the application queue
正解：C
質問 4：
You observe that the number of spilled records from Map tasks far exceeds the number of map output records. Your child heap size is 1GB and your io.sort.mb value is set to 100 MB. How would you tune your io.sort.mb value to achieve maximum memory to disk I/O ratio?
A. Tune the io.sort.mb value until you observe that the number of spilled records equals (or is as close to equals) the number of map output records
B. Increase the io.sort.mb to 1GB
C. For 1GB child heap size an io.sort.mb of 128 MB will always maximize memory to disk I/O
D. Decrease the io.sort.mb value to 0
正解：A
Yawata -
前評判通り、丁寧な解説で読み進めやすかったです。
Pass4Testの問題集CCA-505、12日間の学習で合格できました。