Question

I am using mapreduce to run the program, to submit one job:
I can use following format
./hadoop jar program.jar arguments

in one terminal, this can submit one job, but what if I want to submit 100 jobs? impossible to
open 100 terminals
so I am seeking a batch job submitting methods, thanks!

Answer 1

You call ToolRunner.run(..) in a loop within your main method. Be sure to amend your Tool instance to call Job.submit() rather than Job.waitForCompletion() – ensuring your jobs run more in parallel rather than sequentially (you’re still limited to how many jobs you can run in parallel by your cluster size / config):

public class MyDriver extends Configured implements Tool {
  public static void main(String args[]) {
    for (int x = 0; x < 100; x++) {
      ToolRunner.run(new MyDriver(), args);
    }
  }

  public int run(String args) {
    Job job = new Job(getConf());

    // job set up
    // ...

    job.submit();
  }
}