OverCommitment means virtual machines can use more resources than physical resources.
CPU OverCommitment means you can create virtual machines with vCPU more than your server physical CPU, for example:
- Your server has two socket and each socket has 12 cores and also hyper-threading is enable, so you have 24 physical cores and 48 logical cores totally. But you can create and power on some virtual machines that those virtual machines have more than 48 cores totally.
Memory OverCommitment means your virtual machines can use more memory than the physical machine (the host) has available. For example, you can have a host with 2GB memory and run four virtual machines with 1GB memory each. In that case, the memory is overcommitted.
Advantages vs Disadvantages
With OverCommitment, you can run more virtual machines but if you don’t have sensitive machine.
If you have critical services on virtual machines, you need take care about OverCommitment because it can decrease your machines performance.
How Take Care?
You know, there is many native and third-party applications for monitoring vSphere environment but if you don’t have budget for buy monitoring software, you can use PowerCLI!
There is a free PowerCLI module that you can get information about your infrastructure resource by run them.
You can download it from here.
Also read this blog post for more information.