About the vCenter Operations Heat Map
VMware vCenter Operations Manager offers a very powerful feature called a heat map. A heat map is a set of colored rectangles; the size and color of these rectangles are determined by the linked performance counters. This will give insight information on the two dimensional performance of the objects being analyzed.
Why two dimensional? Well, because you can link up to two counters: one performance counter will influence the size of rectangles in the heat map, the other counter will determine the colors of the rectangles in the heat map. This approach will let you combine and show you the relation between these two performance counters on the selected objects.
Create your own custom heat map
I will illustrate this with an example in which we will create our own custom heat map:
First we have to create a new heat map in vCenter Operations, select the “World” object, choose “Analysis”, “Customize” and select the “Add new configuration” option:
Think of a nice name for this new custom heat map. Now we have to do some configuration, I have used the following settings:
In a short while we will see how these settings will make up our brand new vCenter Operations heat map. A short explanation of these settings is:
- Smallest Box: The smallest box (rectangle) represent the Virtual Machine object;
- Group By: We will group these small boxed (thus, Virtual Machines) by the available hosts, these are the “bigger boxes”;
- I have chosen not to use a third grouping option;
- The color of the boxes will be determined by the value of the CPU Usage (as a percentage);
- The size of the boxes will be determined by the value of the Memory Usage (as a percentage);
- The color and size focus you can set are just for helping to sort and filter the available heatmaps, they have no programmatic meaning as you can read in this post.
View and analyze the heatmap
Now we have created our own heat map, let’s save and evaluate the results. Unfortunately my test lab is not that big, so we will have a rather limited figure…but you will get the idea (click for more detail):
Okay, what’s in the heat map? There are two area’s available: one for the virtual machines available on the first ESXi host, the second area for the virtual machines on the second host. Now look carefully: The size of the virtual machines determines the memory usage as a percentage. So: the bigger the box, the higher the value for memory usage.
The color of the box is influenced by the value for CPU usage, if this value is higher the box will become more red. Notice that a value of 6% CPU usage already results in a almost red box, although this is not something to worry about. By default vCenter Operations will determine values for green to red by evaluating the minimum and maximum values for the counter in the active set. This will result in a better usage of the available colors. You can set you own values for the green-to-red color tint in Heat Map Configuration screen:
You might think to enter 0 as a min value and 100 as the max value; in this case this will result in a lot green boxes which makes the heat map less interesting. Most of the time it’s a good idea to leave the default settings.
Conclusion
I hope this article gives made clear what a heat map is and how you can create your own. Also don’t forget to check the default heat maps included in vCenter Operations 5.6. You can download a 60 day evaluation version of vCenter Operations on the VMware website.
