New VM on Fangtooth running Windows Server 2025. Everything inside the VM feels really sluggish. I just noticed that the VM uses 100% of a single core, even if it’s not doing anything. From running top: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 9624 nobody …

What do you see inside the Windows VM? Is there a process using 100% of a virtual CPU? How many virtual CPU’s did you give to this VM? Wait … [image] ajp_anton: Now, there’s one possibility that I’m shooting myself in the foot by doing nested virtualization So you are running TN as a VM and…

[image] PK1048: I will bet no one has tested that configuration I know the person who could .

Well, you pointed me in the right direction, making me double-check the CPU usage inside the VM. It’s as low as I remembered it, but it seems I messed up the CPU allocation, accidentally giving it “a few” more cores than I intended. Sure enough, there’s one core’s worth of interrupts. I guess this …

Fangtooth VM 100% CPU usage

TrueNAS General

swc-phil May 22, 2025, 1:50pm 3

I know the person who could.

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Fangtooth VM 100% CPU usage

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