VM RAM

[lmannyr]

Hey everyone,

I still consider myself quite new to all FreeNAS and its related uses. Recently loaded up an ubuntu VM to run CrashPlan. This may seem like a dumb question but I have to ask anyway.

When changing RAM amount for a Virtual Machine, does the VM need a reboot or does it take effect immediately. Also, when a VM is assigned an "X" amount of RAM, does that decrease the amount of RAM available to the host by "X" amount as well?

Thanks

 

[Spearfoot]

When changing RAM amount for a Virtual Machine, does the VM need a reboot or does it take effect immediately.

What virtualization platform are you using? VirtualBox? VMware? FreeNAS 9.x jails? FreeNAS 10 bhyve or Docker? Other?

You would need to reboot the VM in all of the virtualization environments I'm familiar with, in order for the RAM change to take effect.

Also, when a VM is assigned an "X" amount of RAM, does that decrease the amount of RAM available to the host by "X" amount as well?

Yes, sir, host RAM is affected by how much memory you allocate to VM's, but this effect is dependent on the environment. VMware allows for over-committing memory, so you might not see much of a net effect unless the VM actually uses all of its memory allotment and has to contend with other VMs for limited resources.

 

[lmannyr]

Using bhyve

I was unsure of when the ram would be available since after "set"ing the ram to a new value, it will show the new value at the shell prompt when viewing the parameters of that VM.


Thanks for the info.