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VM power consumption

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I was hoping that someone could help me on this.

I resently installede new hardware in my unraid server.

I got the Asus kgpe-d16 with dual AMD Opteron 6380 CPU and 256 GB ECC memory.

The system is consuming around 120-130 watts idle, with all disk spun down.


Then comes the problem, when I fire up my windows 10 VM then the system is consuming aound 170-190 watts.

And that is when the VM is loaded and also sitting idle doing nothing.


I can see the CPU usage in unraid, on the dashboard page is around 1-2% so why does it consume like 50-60 watts more when the VM is powered on?

I don't have GFX or other devices passthrough.

The VM is located on the cache drive, så it is not spinning up the array.


Is it normal that a VM would consume so much extra power, even when idle ?

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I have a dual Xeon e5 2670 server that idles at 80w but Windows VM's can push it to 140w when they are updating, have a browser tab open to some spammy web pages (thats most of the pages these days), or doing something silently inside that only Microsoft knows about.  It's not always though, so you should see a well behaved Win10 vm sitting silently at rest and hardly consuming any additional power.  Give it time and see if it stabilizes.


What does the Win10 task manager show for cpu activity from the vm?  I have found that this correlates well with server power usage.


It would be nice to put VM's sleep and be able to waken them remotely, even if they don't have passed through video.  Presently, the only way this can happen is if you go to the unRaid GUI Dashboard or VM screen and rewaken the VM's.  Sleeping VM's don't suck power.

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Well that is the problem, the VM is doing absolutely nothing, I have had it turned on for hours, and the task manager in the vm shows 1-2% cpu usage, and still I can measure a 50-60 w increase in power usage.

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I'd tend to blame Windows like tr0910 suggested. You can use tools to see if its using a lot of resources but you could also install a linux VM and see if it fairs any better. My VMs don't seem to spike power usage much unless they're actually doing something.


I also symlinked my vm folder to my cache drive so I can "hibernate" VMs when they're not in use by storing their memory state to disk. By default unraid uses a ram drive for this area so hibernating will still use ram, it just moves it around in different buckets. It ends up behaving like a suspend to ram sleep state instead of suspend to disk.

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