Paravirtualization interface for Windows 10 Home (SOLVED)

[MarcioAB]

My host is Windows 10 Home and the cpu is very old but still good for my use: Intel Core 2 Quad ( Q9550 )
As far as I understand there is no Hyper-V in the Home edition.
The use of Hyper-V has a catastrophic impact on performance ( cpu @ 100% in the guest and 50% in the host ).
None or minimal interfaces (did not try other interfaces) are usable but also have really poor performance ( more than 2 minutes to open Chrome @ 100% cpu ).
VirtualBox 6.1.4 with Guest Additions installed.

Any suggestions on how to improve performance?

I do not need Windows Pro, but ... will Hyper-V make such a performance improvement that I should consider to upgrade Windows license?
Or maybe, in other words, Is VirtualBox not recommended for Windows Home as a host operating system.

Thank you.

[BillG]

I really don't know what you are trying to say.

As far as I am aware, there is no obvious difference in VirtualBox performance between Windows 10 Home and Pro. I usually use Pro, but I have run these vms in VirtualBox on Home and did not notice any difference.

How does Hyper-V come into the discussion? As you say, Hyper-V cannot run on Windows Home. Why would the ability to run Hyper-V affect the performance of VirtualBox? Actually enabling Hyper-V on Windows Pro will certainly kill VirtualBox at present.

The main things to affect vm performance are memory, CPU and disk performance. Windows 10 needs at least 4G of memory and at least 2 CPUs, whether it is in a physical machine or a vm. To run a Windows 10 guest on a Windows 10 host that adds up to 8G and 4 CPUs for basic performance. To run reasonably well both the host OS and the vm's virtual disk should be on SSD. More memory and more CPUs (and better performance from each CPU) is always better. I run on an i7-7700 with 16G and SSDs and performance is quite good.

With a Q9550 you have 4 CPUs. How much memory do you have? Are you running (at least for the .vdi file) on SSD?

If you are asking whether your vms would run better under Hyper-V on Windows Pro rather than on VirtualBox under VIrtualBox, I would not think so. I have been using both for a long time and have never noticed any speed advantage in using one rather that the other.

Your host is Windows 10 Home. What OS is in the guest?

[MarcioAB]

Guest is Windows 7 with 4 core, 4 GB.
Host is Windows 10 Home with 4 core, 8 GB, running on SSD, vm runs on normal HD.

My question started from the configuration settings.
On "Acceleration" I see "Paravirtualization" as the only configurable item and in the VirtualBox manual, item 10.5. Paravirtualization Providers I see:

Hyper-V:
Presents a Microsoft Hyper-V hypervisor interface which is recognized by Windows 7 and newer operating systems.
Oracle VM VirtualBox's implementation currently supports paravirtualized clocks, APIC frequency reporting, guest debugging, guest crash reporting and relaxed timer checks. This provider is recommended for Windows guests.

If I set paravirtualization to "standard" VirtualBox uses "Hyper-V".
If I set paravirtualization to "legacy" VirtualBox uses "none".
At first, everything seems to be pointing to Hyper-V.

What paravirtualization should I use?

It seems to be "none", and the performance is this one I'm experiencing.
Just to compare, performance in VMware Player is very fast for this "same" vm (this vm was converted from VMware to VirtualBox).

Thank you.

[scottgus1]

this vm was converted from VMware to VirtualBox

You should also be sure to have removed any VMware tools or additions before running the guest in Virtualbox.

The paravirtualization setting is not whether the guest is run by Virtualbox or Hyper-V.

Modern operating systems have been programmed to be aware that they are running in a virtual machine. Updated hypervisors, like Virtualbox, can present a communications channel between the guest OS and Virtualbox to help the guest OS run better when it knows it's in a virtual machine. This channel is the "Paravirtualization interface". Modern Windows expects to communicate to the hypervisor via the Hyper-V protocol. You should let this setting be whatever Virtualbox wants the setting to be when the guest is first made. Change it back to what it was.

This channel is not the big performance-killing Hyper-V that Microsoft likes to turn on for any number of the services WIndows provides, and which kills Virtualbox. That Hyper-V is Microsoft's hypervisor, it is turned on or off by the Windows host's Optional Features, starts itself at the boot of the PC, and can be killed with the 'bcdedit' command and a couple other things, seen in I have a 64bit host, but can't install 64bit guests, posts 2 & 3.

[MarcioAB]

Thank you both.
I think I got the idea.

As I do not remember what interface VirtualBox chooses to change my converted VMware, I will make the full conversion process again and accept whatever interface was chosen.

Anyway, there is a big performance difference here compared with "native" VMware.
Unfortunately, I must use the environment that was created in VMware.
I can not start from the ground and reconstruct it.

[mpack]

As I do not remember what interface VirtualBox chooses to change my converted VMware

No need to reinstall. Windows guests get the Hyper-v para-API or nothing (if Win7 or earlier). Linux guests get KVM or nothing.

If you want people to comment usefully on your performance issues then best stop self diagnosing, and instead provide a VM log. With the VM fully shut down, right click it in the GUI. Select "Show Log" and save "VBox.log" (no other file) to a zip file. Attach the zip here.

[MarcioAB]

Thank you. VBox.log attached.

[mpack]

Reduce assigned cores to 2. You host has 4 cores total, and definitely can't afford to leave 0 for the host OS (which includes VirtualBox itself).

Otherwise, I guess you'll also have to say what aspect of performance seems slow to you.

Please note that there has been a big hardware change, so it's normal for Windows to take a while to settle down after a bunch of update and hardware checks. It's sometimes a good idea to leave it running overnight.

Also, what kind of drive is "H:"? I.e. SATA local, USB flash drive, USB mechanical, USB3 SSD, network drive, etc.

[MarcioAB]

Great. Reducing the guest to 2 cores was a noticeable performance improvement.
Now Chrome is fully loaded in less than 10 seconds, which is OK for my performance expectation for this environment.

H: is a WD 250 GB connected into a SATA 3GB/s.
The real continuous transfer rate is 70 MB/s.

I have other hd that transfer at 90 MB/s (will try that later).

Obs: Strange to me that I did not perceive performance hit in the Host when I gave all the 4 cores to the Guest.
Chrome still came up instantly on the host. But definitively that was the trick here.

EDIT: On the 90 MB/s hd, performance is perceived as equivalent to VMware (on 70 MB/s had). Very good.

Thank you very much.

[mpack]

Thanks for reporting back.