Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

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VirtualboxFan
Posts: 9
Joined: 22. Jan 2019, 23:17

Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

Post by VirtualboxFan »

Testing on Dual EPYC 7742,

Not really noticeable with a few guest vm's, but once you get to 6+ vm's it's very noticeable.

For example: on v6.1.40 I test with 36 guest vm's at 16% CPU usage.
On 7.0.4, I tested with 7 vm's and it already hit 14+% CPU usage.
IndyJones
Posts: 8
Joined: 22. Dec 2016, 14:51

Re: Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

Post by IndyJones »

I have made the same observation. It looks like each VM process (even though the guest is completely idle) consumes around 3% CPU usage according to task manager.
Tested using Windows 10 (22H2 19045.2364) for both, host and guest.
scottgus1
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Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

Post by scottgus1 »

If you both could provide a repeatable and testable method to produce your observations, then post it on the Bugtracker, the devs might be able to pin it down.
mpack
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Re: Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

Post by mpack »

This seems to me to be perfectly normal. Simulating virtual hardware requires CPU. How could it not? And no modern OS is ever completely idle: just look at the Windows task list some time. Nor can you assume that the cost never changes between versions.

Also, I'd seriously want to know on what host PC it is possible to test 36 VMs plus the host all with their own unshared pair of CPU cores.

I would not waste the dev's time with this.
VirtualboxFan
Posts: 9
Joined: 22. Jan 2019, 23:17

Re: Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

Post by VirtualboxFan »

scottgus1 wrote:If you both could provide a repeatable and testable method to produce your observations, then post it on the Bugtracker, the devs might be able to pin it down.
Could you post it on the bug tracker? I can't get on there.

It's definitely repeatable. I just tested the latest version 7.06 running the same exact vm's. 20 vms in and it's already at 38% cpu.

I tried the same vm's again using v6.1.40 and I can run 40 vm's no problem while only using 18% cpu.

Host system

CPU: Dual EPYC 7742
Ram: 500G
Drive: U.3 SSD's


Windows 7 guest.
I'm running the 32-bit 4 wallets on each vm.
https://www.crypto-city.com/element-hyp/wallet/
https://www.crypto-city.com/truckcoin-trk/info
https://www.crypto-city.com/xra-rate-coin/info
https://www.crypto-city.com/bitflowers/wallet/
scottgus1
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Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

Post by scottgus1 »

First you'd have to log into the Bugtracker:
Go to the Bugtracker link.
On the upper right of the web page, click the Login link.
Log In using the same email and password as you use for the Virtualbox forum.
You'll go back to www.virtualbox.org. If the login was successful, you'll see Logout instead on the upper right.
Go to thr Bugtracker link again, You should now be able to make a ticket.

Unfortunately I don't have a host strong enough to try a few decades of VMs. :D
scottgus1
Site Moderator
Posts: 20965
Joined: 30. Dec 2009, 20:14
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Windows, Linux

Re: Host with v7.0.4 seeing significantly higher cpu usage vs v6.1.40

Post by scottgus1 »

I have seen your ticket, and there are no VM logs posted. The ticket is not likely to go far unless zipped logs of VMs when the problem is happening are posted.

FWIW it could be that host Hyper-V is enabled?
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