Performance issues with QEMU-KVM in Windows Guests

[Marco Roccagli]

Hi to all,
i'm detecting huge performance problems in a Windows 11 VM in a QEMU-KVM environment hosted by Ubuntu 22.10.
I have a 12700H intel cpu and Ubuntu is running the stock kernel (5.19.0.26.27).
Normally the virtual machine works without any issues.
Anyway when i do some complex operations that involves the use of all the cores simultaneously (such a Windows update operation or a compilation of huge c++ project) the guest starts to lag (even the mouse can't be moved for several seconds).
I can reproduce always the issue by compiling a specific huge c++ project inside Visual Studio 2022.
At specific point, where visual studio collects all the data and starts to compile, the guest freezes and lags for several seconds and then returns to operate normally.
I've tried to update to the newest 6.0.9 kernel but the problem still persists.
Anyway reverting to the older 5.18.19 there is no such problem even compiling the huge c++ project, So i think that there is something that has changed starting from kernel 5.19.
Any clue for this?

Thanks for your attention

ProblemType: Bug
DistroRelease: Ubuntu 22.10
Package: linux-image-5.19.0-26-generic 5.19.0-26.27
ProcVersionSignature: Ubuntu 5.19.0-26.27-generic 5.19.7
Uname: Linux 5.19.0-26-generic x86_64
ApportVersion: 2.23.1-0ubuntu3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: marcoroccagli 2113 F.... wireplumber
 /dev/snd/seq: marcoroccagli 2110 F.... pipewire
CRDA: N/A
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Fri Dec 2 14:32:58 2022
InstallationDate: Installed on 2022-11-29 (2 days ago)
InstallationMedia: Ubuntu 22.10 "Kinetic Kudu" - Release amd64 (20221020)
MachineType: LENOVO 82RB
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.19.0-26-generic root=UUID=45b01693-19c0-4fc0-b7f2-99912bf9fe6d ro quiet splash intel_iommu=on vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-5.19.0-26-generic N/A
 linux-backports-modules-5.19.0-26-generic N/A
 linux-firmware 20220923.gitf09bebf3-0ubuntu1
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 09/28/2022
dmi.bios.release: 1.46
dmi.bios.vendor: LENOVO
dmi.bios.version: J2CN46WW
dmi.board.asset.tag: NO Asset Tag
dmi.board.name: LNVNB161216
dmi.board.vendor: LENOVO
dmi.board.version: SDK0T76461 WIN
dmi.chassis.asset.tag: NO Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Legion 5 15IAH7H
dmi.ec.firmware.release: 1.46
dmi.modalias: dmi:bvnLENOVO:bvrJ2CN46WW:bd09/28/2022:br1.46:efr1.46:svnLENOVO:pn82RB:pvrLegion515IAH7H:rvnLENOVO:rnLNVNB161216:rvrSDK0T76461WIN:cvnLENOVO:ct10:cvrLegion515IAH7H:skuLENOVO_MT_82RB_BU_idea_FM_Legion515IAH7H:
dmi.product.family: Legion 5 15IAH7H
dmi.product.name: 82RB
dmi.product.sku: LENOVO_MT_82RB_BU_idea_FM_Legion 5 15IAH7H
dmi.product.version: Legion 5 15IAH7H
dmi.sys.vendor: LENOVO

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

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