Database Reference
In-Depth Information
•
Core node
: These are your task and HDFS data nodes. In addition
to specifying the size of each number, you can scale the number of
nodes from 2 to 20 nodes.
•
Task node
: These are worker nodes that perform Hadoop tasks but
do not store data and can be configured in the same manner as core
nodes.
For each of the above node types, you must select the size of the
instance and, in the case of core and task nodes, the number of
instances you want in your cluster. The size of the instance roughly
determines the number of resources (memory, processor, etc.) available
for the instance. For this walk-through, small (
m1.small
) instances are
plenty. As you work beyond this demo, the number of instances and
their size will be dependent on the volume of your data and the data
processing being performed. Use the default settings of 2 core nodes
and 0 task nodes, as shown in
Figure 13.5
,
and then click Continue.
TIP
The size you specify for your nodes will affect your pricing. To keep
size low, use the smallest instance size possible. For more info on
the instance sizes available, visit
http://docs.aws.amazon.com/
