We have an ESXi 6.0 host with vCenter and about 230 VMs.
About 120 are active with a mix of Windows and Linux
I don't have the exact specs, but I believe it is an intel quad core with 512 GB of RAM.
The other day i was looking at the perf monitor and noticed ballooning occurring, which we all know is an indicator of the host running low on RAM.
I also noticed 4-5 VMs showing over 4000 MHz on the host VM tab.
If i remember, each VM has a balloon driver called vmmemctl.sys which is available as part of VMware Tools.
When ESXi runs low on physical RAM, It uses the ballooning driver to determine the how much memory from virtual machines can be get back to prevent the hypervisor swapping.
My question is, what happens if the VMs don't have VMware tools installed?
How is ballooning then handled?
The reason i ask, i see a several VMs on the system without VMware tools running.
Could this be one issue causing high RAM and CPU usage?