Does Proxmox support Host OS Resource Reservation?


Active Member
Apr 15, 2015
planet earth
Hi All,

Does Proxmox support host os resource reservation so it won't overcommit memory?

Like on Microsoft Hyper-V and Citrix XenServer, they have dedicated resources for host OS especially RAM, so it will block VM creation or migration when the new VM will use more than free available resources.

Or is there any way to pre-allocate VM memory so we know the maximum amount memory the VM could use from Proxmox statistic?

Proxmox VE has not a guest resource management which can do what you want.
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Reactions: chrone
found this issue on analyzing proxmox for production use


Proxmox VE has not a guest resource management which can do what you want.

for me it is fully unclear if the query and the answer is matching

1. if I assign MEM resources, lets say 64GB RAM (without ballooning) to a VM via proxmox
does proxmox (KVM) do NOT allocate the full 64GB RAM on starting the VM?
and fails if it cannot allocate the full 64GB to start the VM?
=> cannot imagine that here the resource are not guaranteed?

2. if I assign instead of 64GB, only 32GB min with ballooning, what is the behavior of proxmox in the case too much memory is allocated on the full node?
will proxmox use the ballooning available memory and "kill" processes or caches from any VM to be able to provide overcommited MEM usage?
=> I know this shall never happen, but for understanding...
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