Just a quick question about how the Logical CPUs setting works with regard to assigning them for new VMs in unRAID.  When I got to choose which Logical CPUs to use, is that just choosing how many vCPU's the VM will use or will it only use the exact cores/threads you choose?  I ask because there is no easy way to see what vCPUs are assigned to other VMs without going into each one and if the VM will only use the exact vCPUs assigned, I can see issues when two VMs are using the same vCPUs.  Most of my VM experience is with VMware where the vmkernel is smart enough to determine which vCPUs are free and use them instead of picking individual cores/threads.  Just want to know if KVM (and unRAID) works the same.

Any particular VM will only use the exact CPU cores you assign to it.   You Map the physical cpu cores to particular virtual CPU’s inside the VM.    If more than one running VM has the same cpu core assigned then they will time share it.   Was that the question you were enquiring about?  I think that you are asking about virtual CPU’s - these are local to a particular VM.

1 hour ago, itimpi said:

Any particular VM will only use the exact CPU cores you assign to it.   You Map the physical cpu cores to particular virtual CPU’s inside the VM.    If more than one running VM has the same cpu core assigned then they will time share it.   Was that the question you were enquiring about?  I think that you are asking about virtual CPU’s - these are local to a particular VM.

 

Yes, you answered my question.  So I have to specifically assign different logical CPUs to different VMs if I don't want them to share those CPUs.  It just becomes hard to manage with lots of VMs so I was hoping it wasn't that way.