[vfio-users] Huge performance decrease in VM
Janusz
januszmk6 at gmail.com
Sat Jan 7 12:08:43 UTC 2017
are you sure you weren't using host-passthrough when you were using two
physical cores + hyperthreads? that would screw up topology
On 01/06/2017 11:18 PM, Marius Steffen wrote:
> I already did, IIRC, using two physical cores + their associated
> hyperthreads. Or do you meant using all 4 physical cores? Anyway, I'll
> try isolcpus and fiddling with the options you mentioned.
> Regarding the ck patches, I'm using linux-lqx(Liquorix), with MUQSS
> enabled, to decrease latency (also tried linux-rt, but that didn't
> change anything).
>
> Thanks,
>
> Marius
>
> Am 06.01.2017 um 13:36 schrieb Janusz:
>> use reply to all.
>> don't use all cores, use only half of them, try isolcpus, you can try
>> http://ck-hack.blogspot.com/
>> when you decrease number of cores change host-passthrough to host-model,
>> disable hypervisor.
>> My setup isn't perfect, but I have gpu performance close to native:
>> https://paste.pound-python.org/show/eGf746XJsdtYrA1GEVIl/ but I have i7
>> 6700k so I had to turn off some of hyperv because native were better.
>>
>>
>> On 01/06/2017 01:29 PM, Marius Steffen wrote:
>>> Of course, sorry, I forgot to attach it:
>>>
>>> <domain type='kvm'
>>> xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
>>> <name>game_win_v2</name>
>>> <uuid>5c7150f7-7f7c-4265-acd5-6bed59a10192</uuid>
>>> <memory unit='KiB'>10485760</memory>
>>> <currentMemory unit='KiB'>10485760</currentMemory>
>>> <vcpu placement='static'>8</vcpu>
>>> <cputune>
>>> <vcpupin vcpu='0' cpuset='0'/>
>>> <vcpupin vcpu='1' cpuset='1'/>
>>> <vcpupin vcpu='2' cpuset='2'/>
>>> <vcpupin vcpu='3' cpuset='3'/>
>>> <vcpupin vcpu='4' cpuset='4'/>
>>> <vcpupin vcpu='5' cpuset='5'/>
>>> <vcpupin vcpu='6' cpuset='6'/>
>>> <vcpupin vcpu='7' cpuset='7'/>
>>> </cputune>
>>> <os>
>>> <type arch='x86_64' machine='pc-i440fx-2.6'>hvm</type>
>>> <loader readonly='yes'
>>> type='pflash'>/usr/local/share/ovmf-git/x64/OVMF_CODE.fd</loader>
>>> <nvram>/var/lib/libvirt/qemu/nvram/game_win_v2_VARS.fd</nvram>
>>> </os>
>>> <features>
>>> <acpi/>
>>> <apic/>
>>> <hyperv>
>>> <relaxed state='on'/>
>>> <vapic state='on'/>
>>> <spinlocks state='on' retries='8191'/>
>>> <vendor_id state='on' value='Apfelbaum'/>
>>> </hyperv>
>>> <kvm>
>>> <hidden state='on'/>
>>> </kvm>
>>> <vmport state='off'/>
>>> </features>
>>> <cpu mode='host-passthrough'>
>>> <topology sockets='1' cores='4' threads='2'/>
>>> </cpu>
>>> <clock offset='localtime'>
>>> <timer name='rtc' tickpolicy='catchup'/>
>>> <timer name='pit' tickpolicy='delay'/>
>>> <timer name='hpet' present='no'/>
>>> <timer name='hypervclock' present='yes'/>
>>> </clock>
>>> <on_poweroff>destroy</on_poweroff>
>>> <on_reboot>restart</on_reboot>
>>> <on_crash>restart</on_crash>
>>> <pm>
>>> <suspend-to-mem enabled='no'/>
>>> <suspend-to-disk enabled='no'/>
>>> </pm>
>>> <devices>
>>> <emulator>/usr/sbin/qemu-system-x86_64</emulator>
>>> <disk type='file' device='disk'>
>>> <driver name='qemu' type='raw' cache='none' io='native'/>
>>> <source file='/home/marius/.virt_ssd_speicher/virt_fast.img'/>
>>> <target dev='sda' bus='scsi'/>
>>> <boot order='2'/>
>>> <address type='drive' controller='0' bus='0' target='0'
>>> unit='0'/>
>>> </disk>
>>> <disk type='file' device='disk'>
>>> <driver name='qemu' type='raw' cache='none' io='native'/>
>>> <source file='/media/virt/VM Speicher/win_game_v2.img'/>
>>> <target dev='sdb' bus='scsi'/>
>>> <address type='drive' controller='0' bus='0' target='0'
>>> unit='1'/>
>>> </disk>
>>> <controller type='scsi' index='0' model='virtio-scsi'>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x03'
>>> function='0x0'/>
>>> </controller>
>>> <controller type='virtio-serial' index='0'>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x06'
>>> function='0x0'/>
>>> </controller>
>>> <controller type='pci' index='0' model='pci-root'/>
>>> <controller type='usb' index='0' model='ich9-ehci1'>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x04'
>>> function='0x7'/>
>>> </controller>
>>> <controller type='usb' index='0' model='ich9-uhci1'>
>>> <master startport='0'/>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x04'
>>> function='0x0' multifunction='on'/>
>>> </controller>
>>> <controller type='usb' index='0' model='ich9-uhci2'>
>>> <master startport='2'/>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x04'
>>> function='0x1'/>
>>> </controller>
>>> <controller type='usb' index='0' model='ich9-uhci3'>
>>> <master startport='4'/>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x04'
>>> function='0x2'/>
>>> </controller>
>>> <interface type='network'>
>>> <mac address='52:54:00:97:db:d2'/>
>>> <source network='inet'/>
>>> <model type='rtl8139'/>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x02'
>>> function='0x0'/>
>>> </interface>
>>> <interface type='network'>
>>> <mac address='52:54:00:bb:d0:e5'/>
>>> <source network='host_only'/>
>>> <model type='rtl8139'/>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x09'
>>> function='0x0'/>
>>> </interface>
>>> <input type='mouse' bus='ps2'/>
>>> <input type='keyboard' bus='ps2'/>
>>> <sound model='ac97'>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x07'
>>> function='0x0'/>
>>> </sound>
>>> <hostdev mode='subsystem' type='pci' managed='yes'>
>>> <source>
>>> <address domain='0x0000' bus='0x01' slot='0x00'
>>> function='0x0'/>
>>> </source>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x0a'
>>> function='0x0'/>
>>> </hostdev>
>>> <memballoon model='virtio'>
>>> <address type='pci' domain='0x0000' bus='0x00' slot='0x05'
>>> function='0x0'/>
>>> </memballoon>
>>> </devices>
>>> <qemu:commandline>
>>> <qemu:env name='QEMU_ALSA_DAC_BUFFER_SIZE' value='512'/>
>>> <qemu:env name='QEMU_ALSA_DAC_PERIOD_SIZE' value='170'/>
>>> <qemu:env name='QEMU_AUDIO_DRV' value='alsa'/>
>>> <qemu:env name='QEMU_AUDIO_DAC_FIXED_FREQ' value='44100'/>
>>> <qemu:env name='QEMU_AUDIO_ADC_FIXED_FREQ' value='44100'/>
>>> </qemu:commandline>
>>> </domain>
>>>
>>>
>>> Marius
>>>
>>>
>>> Am 06.01.2017 um 13:24 schrieb Janusz:
>>>> share your vm xml/qemu command, so we can see what you are doing
>>>> wrong.
>>>>
>>>> On 01/06/2017 01:00 PM, Marius Steffen wrote:
>>>>> Hi,
>>>>> I'm running my VM on Arch for quite some time now, with varying
>>>>> success
>>>>> on this hardware:
>>>>>
>>>>> - NVIDIA GTX 1070
>>>>> - 16 GB RAM (10 GB passed through to VM, tested with/without
>>>>> hugepages)
>>>>> - i7 3770 (4 Cores, 4 Hyperthreads, various combinations tested)
>>>>> - virtualized OS is Windows 10 Home x64
>>>>>
>>>>> Arch is using my iGPU (unvirtualized), usally running KDE Plasma
>>>>> 5, but
>>>>> I also tried without running any X-Session.
>>>>>
>>>>> As I recently noticed when upgrading my GPU from a GTX 680 to my
>>>>> current
>>>>> GTX 1070, there's an extremely huge performance impact compared to
>>>>> running on native Windows.
>>>>> When playing Just Cause 3, this was especially noteable: I've
>>>>> often got
>>>>> only 40-50 FPS, compared to 75-120+ FPS in Windows 10, and my GPU
>>>>> being
>>>>> used just about 20% or so in the VM.
>>>>>
>>>>> Is there anything I can do to a) find the cause of this bad
>>>>> performance
>>>>> b) make my VM perform better?
>>>>>
>>>>> Greetings,
>>>>>
>>>>> Marius
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> vfio-users mailing list
>>>>> vfio-users at redhat.com
>>>>> https://www.redhat.com/mailman/listinfo/vfio-users
>
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