Check for memory over allocation (KVM)

Virtualization brought all the benefits of over allocation (using more resources than physically available) to us. And sharing resources like CPU makes a lot of sense if you for example have a daily distributed workload like daily traffic and nightly jobs to generate reports and don’t need all resources at a time. This works great most of the time and is acceptable to slow down your system because of lack of resources sometimes but you definitely don’t want to crash you system because of lack of resources. This is why you usually don’t want over allocate memory. The following script allows you to check this for KVM hypervisor hosts.

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