In VirtualBox 6.1.30 — and other versions as well — when the settings exceed the maximum recommended values for the amount of RAM and/or the amount of CPUs the following message appears:
“Invalid settings detected.”
Even when there is a warning, is it safe ignore that message for these two settings?
I am able to press “OK” button even with that message.
The host OS is going to work practically with no applications explicitly opened and running by the user itself, for example web browser or even some video player.
Therefore the goal is give a good amount of resources to the guest OS but exceeding the maximum recommended limits - in this case only for RAM and CPUs - but knowing that the host is just running with no applications opened by the user itself other than VirtualBox.
So is it safe exceed that limit?
For example:
- If the laptop has 8 CPUs, the maximum recommended is 4, but it would be changed to 6.
- If the laptop has 16GB RAM, the maximum recommended is 10 — really 11 and something more — but it would be changed to 12.
The reasons to exceed this limit are:
- Have faster the guest OS.
- If some software asks for more resources than the guest OS has according the maximum recommended limit.
1 Answer
Based on VMware (I use this and better than VBOX), you can exceed recommended limits. But you cannot exceed physical limits and the machine will likely grind along slowly or not run if you try to exceed limits.
If you have multiple VMs running simultaneously, the total recommended limits cannot exceed the physical limit of ram (Total less Host requirements) or total CPU (less host requirements).
No one machine can have more that the physical limit of ram (Total less about 4 GB for host). So that is, (for ram and including CPU below) the host must be provided with adequate resources over and above what is provided for guest machines).
Be careful with the number of CPUs. I generally use 1 CPU with 2 cores and I am not hindered.
Using more CPUs can sometimes hinder performance and is usually not a good idea. Start small and make sure you have an issue before committing more.
Decent article on this here:
The exact amount of CPU overcommitment a VMware host can accommodate will depend on the VMs and the applications they are running. A general guide for performance of {allocated vCPUs}:{total vCPU} from the Best Practices recommendations is:
1:1 to 3:1 is no problem 3:1 to 5:1 may begin to cause performance degradation 6:1 or greater is often going to cause a problem
