注意：两个版本的api在yarn集群模式都是一样的。
localJobRunner:
cdh:
int numReduceTasks = this.job.getNumReduceTasks();
if (numReduceTasks > 1 || numReduceTasks < 0) {
numReduceTasks = 1;
this.job.setNumReduceTasks(1);
}
Apache :
int numReduceTasks = job.getNumReduceTasks();
用户设置为几 程序就启动几个 可以直接显示出执行效果
x
1
localJobRunner:
2
3
cdh:
4
5
int numReduceTasks = this.job.getNumReduceTasks();
6
if (numReduceTasks > 1 || numReduceTasks < 0) {
7
numReduceTasks = 1;
8
this.job.setNumReduceTasks(1);
9
}
10
11
Apache :
12
int numReduceTasks = job.getNumReduceTasks();
13
用户设置为几 程序就启动几个 可以直接显示出执行效果