The Live! Cluster Utilization dashboard complements the Cluster Performance dashboard. Use this dashboard to view the clusters that are working excessively and are close to their physical limit. This dashboard displays ESXi hosts that have CPU or memory saturation that can lead to performance issues for the VMs running on the host.
This dashboard is designed to complement the Live! Cluster Performance dashboard and it shares design considerations.
How to Use the Dashboard
As this dashboard has an identical design with the Live! Cluster Performance dashboard, it has the same usage procedure. Unlike the heat maps in the Live! Cluster Performance dashboard, the three heat maps in this dashboard have a different scale, reflecting the different nature of the counters.
Logically, memory is a form of storage. It acts as a cache to disk as it is much faster. A high utilization is better, as it indicates that more data is being cached. The ideal situation is when ESXi host Consumed metric is red but ESXi host Ballooned metric is green. When Ballooned is red and Consumed is gray, it means that there was high pressure in the past but it is not there anymore. The reason the ballooned stays red is because the ballooned pages were never requested back.
The ballooned memory counter was selected over the swapped or compressed memory counters as it is a better leading indicator. Since all three can co-exist at the same time, they are displayed in the line chart. Ballooned is displayed in absolute amount and not as a percentage, because the higher the size, higher are the chances for it to impact a VM. If you feel using percentage is easier for your operations, create a super metric to translate the value.
The heat map displays Wastage by a new color. The dark gray color indicates that wastage as capacity is not used. The performance problem due to low utilization can be caused by a bottleneck elsewhere.
Analyze if the ESXi host is contributing. A light gray box indicates that the host is a part of the cluster but there is no utilization. It is possible for the host to be in the maintenance mode or is powered off.
Points to Note
- ESXi host chooses to swap over compression if the compression ratio is less than 4x.
- If the ESXi host's physical NIC is saturated in your environment, then you can add a Network Throughput heat map.