我目前正在运行一项工作,我将地图任务的数量修改为20,但获得更高的数字.我还将reduce任务设置为零,但我仍然得到一个非零的数字.MapReduce作业完成的总时间也不会显示.有人能告诉我我做错了什么.我正在使用此命令
hadoop jar Test_Parallel_for.jar Test_Parallel_for Matrix/test4.txt Result 3 \ -D mapred.map.tasks = 20 \ -D mapred.reduce.tasks =0
输出:
11/07/30 19:48:56 INFO mapred.JobClient: Job complete: job_201107291018_0164
11/07/30 19:48:56 INFO mapred.JobClient: Counters: 18
11/07/30 19:48:56 INFO mapred.JobClient: Job Counters
11/07/30 19:48:56 INFO mapred.JobClient: Launched reduce tasks=13
11/07/30 19:48:56 INFO mapred.JobClient: Rack-local map tasks=12
11/07/30 19:48:56 INFO mapred.JobClient: Launched map tasks=24
11/07/30 19:48:56 INFO mapred.JobClient: Data-local map tasks=12
11/07/30 19:48:56 INFO mapred.JobClient: FileSystemCounters
11/07/30 19:48:56 INFO mapred.JobClient: FILE_BYTES_READ=4020792636
11/07/30 19:48:56 INFO mapred.JobClient: HDFS_BYTES_READ=1556534680 …我目前正在试图弄清楚当你运行MapReduce作业时,通过在代码上的某些位置制作一些system.out.println()会发生什么,但是当作业运行时,知道那些print语句会在我的终端上打印.有人可以帮我弄清楚我到底做错了什么.
import java.io.IOException;
import java.util.StringTokenizer;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.OutputCommitter;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.StatusReporter;
import org.apache.hadoop.mapreduce.TaskAttemptID;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
public class WordCountJob {
public static int iterations;
public static class TokenizerMapper
extends Mapper<Object, Text, Text, IntWritable>{
private final static IntWritable one = new IntWritable(1);
private Text word = new Text();
@Override
public void map(Object key, Text value, Context context
) throws IOException, InterruptedException { …我目前正在开发一个以sql server 2008作为后端的asp.net应用程序.我想让用户能够在SQL语句中指定他们想要过滤的内容.在界面上,我给他们选择以下选项作为下拉列表:等于大于小于等
我想将此作为参数传递给要执行的sql查询.我怎样才能做到最好？
例如;
Select amount, deduction, month from loan where amount @operant 10000;
这@operand是上面下拉列表的返回值= < > <= >=