Ganglia Reports

When you open the Ganglia web reports in a browser, you see an overview of the cluster’s performance, with graphs detailing the load, memory usage, CPU utilization, and network traffic of the cluster. Below the cluster statistics are graphs for each individual server in the cluster. In the preceding job flow creation example, we launched three instances, so in the following reports there are three instance charts showing the cluster data.

The default graph for the node instances is Load, but you can use the Metric drop-down list to change the statistic displayed in the node-instance graphs.

You can drill down into the full set of statistics for a given instance by selecting the node from the drop-down list or by clicking the corresponding node-instance chart.

This opens the Host Overview for the node.

If you scroll down, you can view charts of the full range of statistics collected on the instance.