How to debug where a map-reduce fails? - hadoop

Question

I compile the program it runs successfully but mapper reducer fails; I need help in code to run the mapper and reducer successfully.
I guess there are some parsing issues in the code. Attached are the errors and below that is the code. How can I find the issues to solve this problem?
01/23 03:27:33 INFO mapreduce.Job: map 0% reduce 0%
19/01/23 03:27:50 INFO mapreduce.Job: map 100% reduce 0%
19/01/23 03:27:51 INFO mapreduce.Job: map 0% reduce 0%
19/01/23 03:27:52 INFO mapreduce.Job: Task Id : attempt_1548178978946_0002_m_000000_0, Status : FAILED
Error: java.lang.NumberFormatException: For input string: "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:2043)
at sun.misc.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
at java.lang.Double.parseDouble(Double.java:538)
at java.lang.Double.<init>(Double.java:608)
at com.hadoop.imcdp.MA$Map.partitionData(MA.java:69)
at com.hadoop.imcdp.MA$Map.map(MA.java:58)
at com.hadoop.imcdp.MA$Map.map(MA.java:49)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1762)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
19/01/23 03:28:21 INFO mapreduce.Job: Task Id : attempt_1548178978946_0002_m_000000_1, Status : FAILED
Error: java.lang.NumberFormatException: For input string: "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:2043)
at sun.misc.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
at java.lang.Double.parseDouble(Double.java:538)
at java.lang.Double.<init>(Double.java:608)
at com.hadoop.imcdp.MA$Map.partitionData(MA.java:69)
at com.hadoop.imcdp.MA$Map.map(MA.java:58)
at com.hadoop.imcdp.MA$Map.map(MA.java:49)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1762)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Container killed by the ApplicationMaster.
Container killed on request. Exit code is 143
Container exited with a non-zero exit code 143
19/01/23 03:28:32 INFO mapreduce.Job: Task Id : attempt_1548178978946_0002_m_000000_2, Status : FAILED
Error: java.lang.NumberFormatException: For input string: "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:2043)
at sun.misc.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
at java.lang.Double.parseDouble(Double.java:538)
at java.lang.Double.<init>(Double.java:608)
at com.hadoop.imcdp.MA$Map.partitionData(MA.java:69)
at com.hadoop.imcdp.MA$Map.map(MA.java:58)
at com.hadoop.imcdp.MA$Map.map(MA.java:49)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1762)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Container killed by the ApplicationMaster.
Container killed on request. Exit code is 143
Container exited with a non-zero exit code 143
19/01/23 03:28:51 INFO mapreduce.Job: map 100% reduce 100%
19/01/23 03:28:53 INFO mapreduce.Job: Job job_1548178978946_0002 failed with state FAILED due to: Task failed task_1548178978946_0002_m_000000
Job failed as tasks failed. failedMaps:1 failedReduces:0
19/01/23 03:28:53 INFO mapreduce.Job: Counters: 13
Job Counters
Failed map tasks=4
Killed reduce tasks=1
Launched map tasks=4
Other local map tasks=3
Data-local map tasks=1
Total time spent by all maps in occupied slots (ms)=67635
Total time spent by all reduces in occupied slots (ms)=0
Total time spent by all map tasks (ms)=67635
Total time spent by all reduce tasks (ms)=0
Total vcore-milliseconds taken by all map tasks=67635
Total vcore-milliseconds taken by all reduce tasks=0
Total megabyte-milliseconds taken by all map tasks=69258240
Total megabyte-milliseconds taken by all reduce tasks=0
19/01/23 03:28:53 INFO mapreduce.Job: Running job: job_1548178978946_0002
19/01/23 03:28:53 INFO mapreduce.Job: Job job_1548178978946_0002 running in uber mode : false
19/01/23 03:28:53 INFO mapreduce.Job: map 100% reduce 100%
19/01/23 03:28:53 INFO mapreduce.Job: Task Id : attempt_1548178978946_0002_m_000000_0, Status : FAILED
Error: java.lang.NumberFormatException: For input string: "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:2043)
at sun.misc.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
at java.lang.Double.parseDouble(Double.java:538)
at java.lang.Double.<init>(Double.java:608)
at com.hadoop.imcdp.MA$Map.partitionData(MA.java:69)
at com.hadoop.imcdp.MA$Map.map(MA.java:58)
at com.hadoop.imcdp.MA$Map.map(MA.java:49)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1762)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Container killed by the ApplicationMaster.
Container killed on request. Exit code is 143
Container exited with a non-zero exit code 143
19/01/23 03:28:54 INFO mapreduce.Job: Task Id : attempt_1548178978946_0002_m_000000_1, Status : FAILED
Error: java.lang.NumberFormatException: For input string: "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:2043)
at sun.misc.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
at java.lang.Double.parseDouble(Double.java:538)
at java.lang.Double.<init>(Double.java:608)
at com.hadoop.imcdp.MA$Map.partitionData(MA.java:69)
at com.hadoop.imcdp.MA$Map.map(MA.java:58)
at com.hadoop.imcdp.MA$Map.map(MA.java:49)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1762)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Container killed by the ApplicationMaster.
Container killed on request. Exit code is 143
Container exited with a non-zero exit code 143
19/01/23 03:28:54 INFO mapreduce.Job: Task Id : attempt_1548178978946_0002_m_000000_2, Status : FAILED
Error: java.lang.NumberFormatException: For input string: "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:2043)
at sun.misc.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
at java.lang.Double.parseDouble(Double.java:538)
at java.lang.Double.<init>(Double.java:608)
at com.hadoop.imcdp.MA$Map.partitionData(MA.java:69)
at com.hadoop.imcdp.MA$Map.map(MA.java:58)
at com.hadoop.imcdp.MA$Map.map(MA.java:49)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1762)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Container killed by the ApplicationMaster.
Container killed on request. Exit code is 143
Container exited with a non-zero exit code 143
19/01/23 03:28:54 INFO mapreduce.Job: Job job_1548178978946_0002 failed with state FAILED due to: Task failed task_1548178978946_0002_m_000000
Job failed as tasks failed. failedMaps:1 failedReduces:0
19/01/23 03:28:54 INFO mapreduce.Job: Counters: 13
Job Counters
Failed map tasks=4
Killed reduce tasks=1
Launched map tasks=4
Other local map tasks=3
Data-local map tasks=1
Total time spent by all maps in occupied slots (ms)=67635
Total time spent by all reduces in occupied slots (ms)=0
Total time spent by all map tasks (ms)=67635
Total time spent by all reduce tasks (ms)=0
Total vcore-milliseconds taken by all map tasks=67635
Total vcore-milliseconds taken by all reduce tasks=0
Total megabyte-milliseconds taken by all map tasks=69258240
Total megabyte-milliseconds taken by all reduce tasks=0
code of moving average example
public class MA extends Configured implements Tool{
// For production the windowlength would be a commandline or other argument
static double windowlength = 3.0;
static int thekey = (int)windowlength/2;
// used for handling the circular list.
static boolean initialised=false;
// Sample window
static ArrayList<Double> window = new ArrayList<Double>() ;
// The Map method processes the data one point at a time and passes the circular list to the
// reducer.
public static class Map extends Mapper<LongWritable, Text, Text, Text> {
private final static IntWritable one = new IntWritable(1);
private Text word = new Text();
public void map(LongWritable key, Text value, Context context
) throws IOException , InterruptedException
{
double wlen = windowlength;
// creates windows of samples and sends them to the Reducer
partitionData(value, context, wlen);
}
// Create sample windows starting at each sata point and sends them to the reducer
private void partitionData(Text value,
Context context, double wlen)
throws IOException , InterruptedException {
String line = value.toString();
// the division must be done this way in the mapper.
Double ival = new Double(line)/wlen;
// Build initial sample window
if(window.size() < windowlength)
{
window.add(ival);
}
// emit first window
if(!initialised && window.size() == windowlength)
{
initialised = true;
emit(thekey, window, context);
thekey++;
return;
}
// Update and emit subsequent windows
if(initialised)
{
// remove oldest datum
window.remove(0);
// add new datum
window.add(ival);
emit(thekey, window, context);
thekey++;
}
}
}
// Transform list to a string and send to reducer. Text to be replaced by ObjectWritable
// Problem: Hadoop apparently requires all output formats to be the same so
// cannot make this output collector differ from the one the reducer uses.
public static void emit(int key, ArrayList<Double> value, Context context) throws IOException , InterruptedException
{
Text tx = new Text();
tx.set(new Integer(key).toString());
String outstring = value.toString();
// remove the square brackets Java puts in
String tidied = outstring.substring(1,outstring.length()-1).trim();
Text out = new Text();
out.set(tidied);
context.write(tx,out);
}
public static class Reduce extends Reducer<Text, Text, Text, Text>
{
public void reduce(Text key,
Iterator<Text> values,
Context context
) throws IOException , InterruptedException
{
while (values.hasNext())
{
computeAverage(key, values, context);
}
}
// computes the average of each window and sends to ouptut collector.
private void computeAverage(Text key, Iterator<Text> values,
Context context)
throws IOException , InterruptedException {
double sum = 0;
String thevalue = values.next().toString();
String[] thenumbers = thevalue.split(",");
for( String temp: thenumbers)
{
// need to trim the string because the constructor does not trim.
Double ds = new Double(temp.trim());
sum += ds;
}
Text out = new Text();
String outstring = Double.toString(sum);
out.set(outstring);
context.write (key, out);
}
}
#Override
public int run(String[] args) throws Exception {
Configuration conf = new Configuration();
args = new GenericOptionsParser(conf, args).getRemainingArgs();
String input = args[0];
String output = args[1];
Job job = new Job(conf, "MA");
job.setJarByClass(MA.class);
job.setInputFormatClass(TextInputFormat.class);
job.setMapperClass(Map.class);
job.setMapOutputKeyClass(Text.class);
job.setMapOutputValueClass(Text.class);
job.setCombinerClass(Reduce.class);
job.setReducerClass(Reduce.class);
job.setOutputFormatClass(TextOutputFormat.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(Text.class);
FileInputFormat.setInputPaths(job, new Path(input));
Path outPath = new Path(output);
FileOutputFormat.setOutputPath(job, outPath);
outPath.getFileSystem(conf).delete(outPath, true);
job.waitForCompletion(true);
return (job.waitForCompletion(true) ? 0 : 1);
}
public static void main(String[] args) throws Exception {
int exitCode = ToolRunner.run(new MA(), args);
System.exit(exitCode);
}
// public static void main(String[] args) throws Exception {
// JobConf conf = new JobConf(MA.class);
// conf.setJobName("MA");
// conf.setOutputKeyClass(Text.class);
// conf.setOutputValueClass(Text.class);
// conf.setMapperClass(Map.class);
// conf.setCombinerClass(Reduce.class);
// conf.setReducerClass(Reduce.class);
// conf.setInputFormat(TextInputFormat.class);
// conf.setOutputFormat(TextOutputFormat.class);
// FileInputFormat.setInputPaths(conf, new Path(args[0]));
// FileOutputFormat.setOutputPath(conf, new Path(args[1]));
// FileInputFormat.setInputPaths(conf, new Path("input/movingaverage.txt"));
// FileOutputFormat.setOutputPath(conf, new Path("output/smoothed"));
// JobClient.runJob(conf);
// }
}

Answer 1

Double ival = new Double(line)/wlen;
is throwing the error, as line is 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20, which doesn't parse into a Double. Assuming you want each of these numbers to be a double, you need to do:
List<Double> ivals = new ArrayList<>();
String[] numbers = line.split(",");
for (int i = 0; i < numbers.length(); i++) {
ivals.add(new Double(numbers[i])/wlen);
}