O'Reilly logo

Hadoop Operations and Cluster Management Cookbook by Shumin Guo

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Setting proper number of map and reduce slots for the TaskTracker

The number of map and reduce slots determines the number of concurrent map/reduce tasks for a TaskTracker, which forks multiple JVMs to run these tasks. In this recipe, we will give you a general view of setting proper number of these slots for the TaskTracker.

Getting ready

We assume that the Hadoop cluster has been properly configured and all the daemons are running without any issues.

Log in from the Hadoop cluster administrator machine to the cluster master node using the following command:

ssh hduser@master

How to do it...

Use the following steps to configure map/reduce slots for a TaskTracker:

  1. Stop the MapReduce cluster with the following command:
    stop-mapred.sh
    
  2. Configure the map ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required