virtualbox.org

Hi,
I really don't recommend to make the VirtualBox updated to ver. 6 on Windows 10 host with Windows XP (SP3) guest system. It works very slowly and after several settings changes I have done in the host, it became hopeless (and useless) for now.
Starting Win XP loads the host processor nearly to 30% or even more, but the guest works very very slowly.

My host is working with Windows 10 Pro (2004), Intel i7-7th gen. with enough either RAM and disk space. Before update to VirtualBox ver. 6 everything was working smoothly. After update (even reinstall) and GA's installation the guest machine abilities are not acceptable. It doesn't matter whether the Hyper-V is on or off in the host.

BTW: Same problem, or even worse (guest seems to be locked during startup) I do have with Windows 10 as guest.

Maybe somebody who is visiting this forum, could help?

Hi,
in my case neither the Hyper-V set off or core's reduction brings no better operation.
My host is working with Windows 10 Pro (2004), Intel i7-7th gen. with enough either RAM and disk space.
As a guest I do have the Windows 10. Before update to VirtualBox ver. 6 everything was working smoothly. After update (even reinstall) and GA's installation the guest machine abilities are not acceptable - seems to be locked during startup.
The host processor load is nearly 30% or more.

Maybe somebody who is visiting this forum, could help? Thank you in advance.

I am running XP on both 6.0.x and 6.1.x on two Windows 10 hosts just fine.

Rick_J_Rick wrote:It doesn't matter whether the Hyper-V is on or off in the host

There's turning it off, then there's really turning it off.

Start the guest from full power off, not save-state. Run until you see the problem happen, then shut down the guest from within the guest OS if possible. If not possible, close the Virtualbox window for the guest with the Power Off option set.

Then right-click the guest in the main Virtualbox window's guest list, choose Show Log.

Search the far left tab's log for this text:

Attempting fall back to NEM

If you find it, Hyper-V is enabled and needs to be disabled. See HMR3Init: Attempting fall back to NEM (Hyper-V is active). Version 6.1.16 might fix this. If you're on an earlier version, try it.

If you don't find that text, save the far left tab's log, zip the log file, and post the zip file, using the forum's Upload Attachment tab.

I know these two posts are on different subjects but they might be solved by the same method as shown above. We'll consider the differences after pinning down what the log says.

Hi and many thanks to scottgus1 for the answer.

In my work with VirtualBox I have been taking care on the Hyper-V issue making it set to off really. I learned about it during the time when have been using the VirtualBox ver. 5.

Actually I do have the VirtualBox ver. 6.1.16 and checking the logs generated by Windows XP SP3 or Windows 10 guest machines can find the lines like:

00:00:03.366162 HM: HMR3Init: Attempting fall back to NEM: VT-x is not available
00:00:03.415162 NEM: WHvCapabilityCodeHypervisorPresent is TRUE, so this might work...
00:00:03.415172 NEM: WHvCapabilityCodeExtendedVmExits = 0x00000000000003ff
00:00:03.415177 NEM: fExtendedMsrExit: 1
00:00:03.415204 NEM: fExtendedCpuIdExit: 1
00:00:03.415207 NEM: fExtendedXcptExit: 1
00:00:03.415210 NEM: Warning! Unknown VM exit definitions: 0x3ff
00:00:03.415216 NEM: Warning! Unknown feature definitions: 0x7f
00:00:03.415219 NEM: Supported exception exit bitmap: 0xf7dfb
00:00:03.415225 NEM: WHvCapabilityCodeProcessorVendor = 1 - Intel
00:00:03.415234 NEM: WHvCapabilityCodeProcessorFeatures = 0x000178ffe7f7859f

They show that the Hyper-V functionality is really off, I suppose. For the test I have set it on (also really, from command line) and than set it off again after unsuccessful results observed.

Today have had a bit more time to play with this issue and installed the VirtualBox 6.1.16 software on the clean like host system - after removing the software installed before and all the registry settings created by it. After this installation the both Windows guests running well, like it was before. In the log files created I can't find the lines with "Attempting..." text.

In my opinion the previously described issue with very slowly working Windows guests creating significant host system load is created by some problem in the software updateing mechanism. I do remember me that the very early version of VirtualBox 6 I have installed on the clean like host system after removing all details created by version 5. The Windows guests were working fine afterwards, but later, after software updated again to 6.1... the problem appeared. This is something to be announced to the developers at Oracle, I guess.

Rick_J_Rick wrote:They show that the Hyper-V functionality is really off, I suppose.

The opposite is true: WHvCapabilityCodeHypervisorPresent is a function that is provided by the Windows Hyper-V implementation.

fth0 is correct. Any vbox.log with the "Attempting fall back to NEM" lines on a Windows host means that Hyper-V is enabled. There are many things, even on Windows Home, that use Hyper-V, not just Hyper-V VMs.

The Virtualbox devs are working on getting Virtualbox to work under Hyper-V, but it's not all there yet. It is easier for now to turn Hyper-V off when you want to use Virtualbox.