当减速器达到67％时我们得到超时异常，我认为这是在排序阶段之后和减少阶段之前。请告知我们应该寻找哪些参数来解决问题。
16/06/15 16:58:13 INFO mapreduce.Job: map 100% reduce 0%
16/06/15 16:58:23 INFO mapreduce.Job: map 100% reduce 24%
16/06/15 16:59:05 INFO mapreduce.Job: map 100% reduce 28%
16/06/15 16:59:08 INFO mapreduce.Job: map 100% reduce 30%
16/06/15 16:59:39 INFO mapreduce.Job: map 100% reduce 33%
16/06/15 17:00:09 INFO mapreduce.Job: map 100% reduce 52%
16/06/15 17:00:12 INFO mapreduce.Job: map 100% reduce 67%
16/06/15 17:05:42 INFO mapreduce.Job: Task Id : attempt_1465992294703_0001_r_000000_2, Status : FAILED
驱动程序类
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.CSVLineRecordReader;
import org.apache.hadoop.mapreduce.lib.input.CSVNLineInputFormat;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
public class ExchgLogsTransposeDriver extends Configured implements Tool {
public int run(String[] args) throws Exception {
@SuppressWarnings("deprecation")
Configuration conf = getConf();
String outPath=null;
String inPath=null;
if(args==null ||args.length==0){
inPath="C:\\HadoopWS\\infile\\";
outPath="C:\\HadoopWS\\outfile\\";
}else{
inPath=args[0];
outPath=args[1];
}
Path output =new Path(outPath);
Path input =new Path(inPath);
FileSystem hdfs = FileSystem.get(conf);
if (hdfs.exists(output)) {
hdfs.delete(output, true);
}
conf.set(CSVLineRecordReader.FORMAT_DELIMITER, "\"");
conf.set(CSVLineRecordReader.FORMAT_SEPARATOR, ",");
conf.setInt(CSVNLineInputFormat.LINES_PER_MAP, 500000);
conf.setBoolean(CSVLineRecordReader.IS_ZIPFILE, false);
Job job = new Job(conf);
job.setJarByClass(ExchgLogsTransposeDriver.class);
job.setMapperClass(ExchgLogsMapper.class);
job.setMapOutputKeyClass(CompositeKey.class);
job.setMapOutputValueClass(CompositeWritable.class);
// job.setNumReduceTasks(2);
job.setMapSpeculativeExecution(true);
job.setPartitionerClass(ActualKeyPartitioner.class);
job.setGroupingComparatorClass(ActualKeyGroupingComparator.class);
job.setSortComparatorClass(CompositeKeyComparator.class);
job.setReducerClass(ExchgLogsReducer.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(CompositeWritable.class);
job.getConfiguration().set("mapreduce.output.basename", input.getName());
job.getConfiguration().set("mapreduce.map.output.compress", "true");
// job.getConfiguration().set("mapreduce.map.output.compress.codec", "com.hadoop.compression.lzo.LzoCodec");
job.setInputFormatClass(CSVNLineInputFormat.class);
job.setOutputFormatClass(TextOutputFormat.class);
FileInputFormat.setInputDirRecursive(job, true);
FileInputFormat.addInputPath(job, new Path(inPath));
FileOutputFormat.setOutputPath(job, new Path(outPath));
return job.waitForCompletion(true) ? 0 : 1;
}
public static void main(String args[]) throws Exception {
System.exit(ToolRunner.run(new ExchgLogsTransposeDriver(), args));
}
}
减速机等级
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.TimeUnit;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;
public class ExchgLogsReducer extends Reducer<CompositeKey, CompositeWritable, NullWritable, Text> {
Log log = LogFactory.getLog(ExchgLogsReducer.class);
public static final String NEW = "NEW";
public static final String FW = "FW";
public static final String RE = "RE";
public static final int ZERO = 0;
Text res = new Text();
@Override
public void reduce(CompositeKey key, Iterable<CompositeWritable> value, Context context)
throws IOException, InterruptedException {
List<CompositeValueObj> cache = new ArrayList<CompositeValueObj>();
StringBuilder response = new StringBuilder();
Iterator<CompositeWritable> it = value.iterator();
while (it.hasNext()) {
CompositeWritable currWritable = new CompositeWritable();
currWritable = it.next();
CompositeValueObj obj = new CompositeValueObj();
obj.setRecepient((currWritable.getRecepient().toString()));
obj.setSender(currWritable.getSender().toString());
obj.setType(currWritable.getType().toString());
obj.setTimestamp(currWritable.getTimestamp().toString());
cache.add(obj);
// System.out.println(new Text(" "+"\t" + obj.getRecepient() + "\t"
// + obj.getSender() + "\t" +obj.getType()+ "\t" +
// obj.getTimestamp()));
}
for (int i = 0; i < cache.size(); i++) {
CompositeValueObj currobj = cache.get(i);
String receiver = currobj.getRecepient().toString();
String origSender = currobj.getSender().toString();
String dateFrom = currobj.getTimestamp().toString();
System.out.println(key.getSubject() + " " + "i==>" + i + cache.size());
for (int j = i + 1; j < cache.size(); j++) {
response = new StringBuilder(key.getSubject()).append(",").append(receiver).append(",");
CompositeValueObj nextObj = cache.get(j);
System.out.println(key.getSubject() + " " + "j==>" + j);
String dateTo = nextObj.getTimestamp().toString();
String newSender = nextObj.getSender().toString();
String newRecepient = nextObj.getRecepient().toString();
String mailType = nextObj.getType().toString();
// System.out.println(mailType+ "==>"+receiver+
// "==>"+newRecepient);
if (receiver.equals(newRecepient)) {
response.append(origSender).append(",");
response.append("N,0,0,").append(dateFrom);
break;
}
if (receiver.equals(newSender) && ((mailType.equals(RE) || (mailType.equals(FW))))) {
if (mailType.equals(RE)) {
response.append(origSender).append(",");
response.append("Y,");
response.append(getTimeDiff(dateFrom, dateTo));
response.append(",0,").append(dateTo);
break;
}
if (mailType.equals(FW)) {
response.append(origSender).append(",");
response.append("Y,0,");
response.append(getTimeDiff(dateFrom, dateTo));
response.append(",").append(dateTo);
break;
}
} else {
response.append(origSender).append(",");
response.append("N,0,0,").append(dateFrom);
}
}
if (i + 1 == cache.size()) {
response = new StringBuilder(key.getSubject()).append(",").append(receiver).append(",");
response.append(origSender).append(",");
response.append("N,0,0,").append(dateFrom);
}
res.set(response.toString());
// System.err.println(key.getSubject()+new
// Text(response.toString()));
context.write(NullWritable.get(), res);
}
}
private static double getTimeDiff(String date1, String date2) {
double diff = 0;
double weekend = 0;
boolean isWEchain=false;
boolean isWESent=false;
if (date1 == null || date2 == null) {
return 0;
}
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
try {
Date from = sdf.parse(date1);
Date to = sdf.parse(date2);
Calendar cal1 = Calendar.getInstance();
Calendar cal2 = Calendar.getInstance();
cal1.setTime(from);
cal2.setTime(to);
int noOfDaysWE = 0;
System.out.println(cal1.get(Calendar.DAY_OF_WEEK));
System.out.println(cal2.get(Calendar.DAY_OF_WEEK));
if ((((Calendar.FRIDAY == cal1.get(Calendar.DAY_OF_WEEK))
|| (Calendar.SATURDAY == cal1.get(Calendar.DAY_OF_WEEK)))
&& ((Calendar.FRIDAY == cal2.get(Calendar.DAY_OF_WEEK))
|| (Calendar.SATURDAY == cal2.get(Calendar.DAY_OF_WEEK))))
) {
isWEchain =true;
}else if((((Calendar.FRIDAY == cal1.get(Calendar.DAY_OF_WEEK))
|| (Calendar.SATURDAY == cal1.get(Calendar.DAY_OF_WEEK)))
&& (((Calendar.FRIDAY != cal2.get(Calendar.DAY_OF_WEEK))
&& (Calendar.SATURDAY != cal2.get(Calendar.DAY_OF_WEEK)))))){
isWESent=true;
if(Calendar.FRIDAY == cal1.get(Calendar.DAY_OF_WEEK)){
cal1.add(Calendar.DATE, 1);
}
cal1.set(Calendar.HOUR,20);
cal1.set(Calendar.MINUTE,0);
cal1.set(Calendar.SECOND,0);
cal1.set(Calendar.MILLISECOND,0);
}
System.out.println(cal1.getTime());
System.out.println(cal2.getTime());
System.out.println(isWESent);
diff=cal2.getTimeInMillis() - cal1.getTimeInMillis();
if(diff < 0 ){
return 0;
}
while (cal1.before(cal2)) {
if ((Calendar.FRIDAY == cal1.get(Calendar.DAY_OF_WEEK))
|| (Calendar.SATURDAY == cal1.get(Calendar.DAY_OF_WEEK))) {
noOfDaysWE++;
}
cal1.add(Calendar.DATE, 1);
}
if (noOfDaysWE != 0) {
weekend = TimeUnit.DAYS.toMillis(noOfDaysWE);
}
if(isWEchain && (noOfDaysWE <= 2)){
return 0;
}
System.out.println(diff);
diff = diff - weekend;
} catch (ParseException e) {
return 0;
}
if (diff != 0)
return diff / 1000;
else
return 0;
}
public static void main(String[] a) {
System.out.println(getTimeDiff("2016-06-03T19:41:48.781Z", "2016-06-05T07:21:01.000Z"));
}
}
答案 0 :(得分：1)
请mapred.task.timeout查看mapred-site.xml中的毫秒数。
更改属性后，必须重新启动所有转换器。（作业+任务）
提示：如果要在运行时打印所有配置以检查是否已应用，请使用以下驱动程序中的代码段。 例如：
final JobConf conf = new JobConf(config, this.getClass());
try {
conf.writeXml(System.out);
} catch (final IOException e) {
e.printStackTrace();
}
答案 1 :(得分：1)
从67％-100％开始执行实际的减少代码，因此没有任何减少任务完成。可能有太多的数据流向reducer，或者可能存在某种无限循环。
答案 2 :(得分：1)
循环内的reducer代码中有很少的sysout，它们写了很多日志，删除它们后，reducer在几分钟内就完成了。！