Tier 1 compute
Let's recap from Chapter 5, Capacity Monitoring, what we need to produce to monitor capacity in tier 1 compute:
- A line chart showing the total number of vCPUs left in the cluster
- A line chart showing the total number of vRAM left in the cluster
- A line chart showing the total number of VMs left in the cluster
Tier 1 compute – CPU
Let's look at the first line chart. The number of vCPUs left is essentially supply and demand. The supply and demand can be defined as the following:
- Supply = (The total physical cores of all ESXi hosts) - (HA buffer)
- Demand = The total vCPUs for all the VMs
On the supply side, we can choose physical cores or physical threads. One will be conservative while the other will be aggressive. The ideal number is 1.5 times the physical core, as that's the estimated performance improvement from Hyper-Threading.
My recommendation is to count the cores, not the threads. There are two reasons for this:
- This is tier 1, your highest and best tier...
