Hadoop之MapReduce01【自带wordcount案例】

 hadoop fs -mkdir -p /wordcount/input
 hadoop fs -put a.txt /wordcount/input/

start-yarn.sh

hadoop jar hadoop-mapreduce-examples-2.6.5.jar wordcount /wordcount/input/ /wordcount/output

[root@hadoop-node01 mapreduce]# hadoop jar hadoop-mapreduce-examples-2.6.5.jar wordcount /wordcount/input/ /wordcount/output
19/04/02 23:06:03 INFO client.RMProxy: Connecting to ResourceManager at hadoop-node01/192.168.88.61:8032
19/04/02 23:06:07 INFO input.FileInputFormat: Total input paths to process : 1
19/04/02 23:06:09 INFO mapreduce.JobSubmitter: number of splits:1
19/04/02 23:06:09 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1554217397936_0001
19/04/02 23:06:10 INFO impl.YarnClientImpl: Submitted application application_1554217397936_0001
19/04/02 23:06:11 INFO mapreduce.Job: The url to track the job: http://hadoop-node01:8088/proxy/application_1554217397936_0001/
19/04/02 23:06:11 INFO mapreduce.Job: Running job: job_1554217397936_0001
19/04/02 23:06:30 INFO mapreduce.Job: Job job_1554217397936_0001 running in uber mode : false
19/04/02 23:06:30 INFO mapreduce.Job:  map 0% reduce 0%
19/04/02 23:06:46 INFO mapreduce.Job:  map 100% reduce 0%
19/04/02 23:06:57 INFO mapreduce.Job:  map 100% reduce 100%
19/04/02 23:06:58 INFO mapreduce.Job: Job job_1554217397936_0001 completed successfully
19/04/02 23:06:59 INFO mapreduce.Job: Counters: 49
	File System Counters
		FILE: Number of bytes read=133
		FILE: Number of bytes written=214969
		FILE: Number of read operations=0
		FILE: Number of large read operations=0
		FILE: Number of write operations=0
		HDFS: Number of bytes read=240
		HDFS: Number of bytes written=79
		HDFS: Number of read operations=6
		HDFS: Number of large read operations=0
		HDFS: Number of write operations=2
	Job Counters 
		Launched map tasks=1
		Launched reduce tasks=1
		Data-local map tasks=1
		Total time spent by all maps in occupied slots (ms)=11386
		Total time spent by all reduces in occupied slots (ms)=9511
		Total time spent by all map tasks (ms)=11386
		Total time spent by all reduce tasks (ms)=9511
		Total vcore-milliseconds taken by all map tasks=11386
		Total vcore-milliseconds taken by all reduce tasks=9511
		Total megabyte-milliseconds taken by all map tasks=11659264
		Total megabyte-milliseconds taken by all reduce tasks=9739264
	Map-Reduce Framework
		Map input records=24
		Map output records=27
		Map output bytes=236
		Map output materialized bytes=133
		Input split bytes=112
		Combine input records=27
		Combine output records=12
		Reduce input groups=12
		Reduce shuffle bytes=133
		Reduce input records=12
		Reduce output records=12
		Spilled Records=24
		Shuffled Maps =1
		Failed Shuffles=0
		Merged Map outputs=1
		GC time elapsed (ms)=338
		CPU time spent (ms)=2600
		Physical memory (bytes) snapshot=283582464
		Virtual memory (bytes) snapshot=4125011968
		Total committed heap usage (bytes)=137363456
	Shuffle Errors
		BAD_ID=0
		CONNECTION=0
		IO_ERROR=0
		WRONG_LENGTH=0
		WRONG_MAP=0
		WRONG_REDUCE=0
	File Input Format Counters 
		Bytes Read=128
	File Output Format Counters 
		Bytes Written=79

[root@hadoop-node01 mapreduce]# hadoop fs -cat /wordcount/output/part-r-00000
1	1
2	1
3	1
a	4
b	2
c	1
hadoop	3
hdfs	2
hello	2
java	7
mapreduce	1
wordcount	2