[vfio-users] Hyperthreading and kvm

Jonathan Panozzo jonp at lime-technology.com
Sat Aug 22 17:21:16 UTC 2015 

You actually don’t need to use a spice server to use QXL.  You can use QXL as an alternative graphics adapter and still use VNC as the remote graphics server.

> On Aug 22, 2015, at 12:17 PM, José Ramón Muñoz Pekkarinen <koalinux at gmail.com> wrote:
> 
> 	Hi,
> 
> 	Is it any other like vmware valid? I didn't try to install spice in my 
> setup.
> 
> 	BR.
> 
> 	José.
> 
> On Saturday 22 August 2015 20:11:01 Blank Field wrote:
>>> -vga cirrus
>> 
>> ...
>> dude.
>> You need QXL-VGA. Cirrus is.. deprecated, i think.
>> 
>> 2015-08-22 20:02 GMT+03:00 José Ramón Muñoz <koalinux at gmail.com>:
>>>        Hi,
>>> 
>>>        I gave it a try today with no success. The launch command was:
>>> /qemu-system-x86_64 -enable-kvm -vga cirrus -cpu host -smp
>>> 4,cores=4,threads=1
>>> -m 4096 \
>>> 
>>>        -netdev user,id=user.0 -device e1000,netdev=user.0 \
>>>        -usb -usbdevice tablet \
>>>        -drive
>>>        if=pflash,format=raw,readonly,file=/usr/share/edk2.git/ovmf-
>>> 
>>> x64/OVMF_CODE-with-csm.fd \
>>> 
>>>        -drive if=pflash,format=raw,file=/usr/share/edk2.git/ovmf-
>>> 
>>> x64/Windows_ovmf_vars_x64.fd \
>>> 
>>>        -drive
>>> 
>>> file=/dev/koalita/koalitavm,format=raw,cache=none,aio=native,if=virtio
>>> 
>>>        I tried to launch it using the virtio disk, the ide disk, and
>>> 
>>> empty disk
>>> with the windows 7 installer, and even without disk to see if the cdrom
>>> launchs ok.
>>> 
>>>        Best regards.
>>> 
>>>        José.
>>> 
>>> On Wednesday 19 August 2015 23:23:43 Blank Field wrote:
>>>> The need of Q35 is overrated. Usually you need it for booting from sata
>>>> controllers or something.
>>>> For our use 440fx works better.
>>>> I've used windows 7 on my machine. All you need to do is to follow the
>>> 
>>> OVMF
>>> 
>>>> whitepaper:
>>>> http://www.linux-kvm.org/downloads/lersek/ovmf-whitepaper-c770f8c.txt
>>>> 
>>>> 2015-08-19 20:35 GMT+03:00 José Ramón Muñoz <koalinux at gmail.com>:
>>>>>        Hi,
>>>>> 
>>>>>        Sorry for not replying to all, I wrote from the phone and
>>>>>        sometimes
>>>>> 
>>>>> happens.
>>>>> 
>>>>>        About the ovmf stuff, I would give it a try just in case I
>>> 
>>> didn't
>>> 
>>>>> read the
>>>>> Alex Williamson post that explained that I need windows > win7 to be
>>> 
>>> able
>>> 
>>>>> to
>>>>> use it. I'm still not planning to upgrade it to windows 10.
>>>>> 
>>>>>        How about q35? I tried to launch it but it seems to yield a
>>>>> 
>>>>> beautiful
>>>>> BSOD because of the ati drivers not being expanded. Do anyone uses it
>>>>> regularly?
>>>>> 
>>>>>        BR.
>>>>> 
>>>>>        José.
>>>>> 
>>>>> On Wednesday 19 August 2015 20:12:23 Blank Field wrote:
>>>>>> Please, use the reply-all button. Include "vfio-users at redhat.com"
>>>>> 
>>>>> address
>>>>> 
>>>>>> in the "to:" field.
>>>>>> 
>>>>>>>   So, I got it right that using OVMF my setup can work reliably?
>>>>>>>   I
>>>>>>>   was
>>>>>> 
>>>>>> considering to build it but it seems to be not so straight forward
>>>>>> in
>>>>>> Gentoo.
>>>>>> 
>>>>>> I haven't tried doing this on gentoo, but you can try using "alien"
>>> 
>>> to
>>> 
>>>>> use
>>>>> 
>>>>>> RPMs from kraxel.org
>>>>>> https://www.kraxel.org/repos/
>>>>>> Also, i recall there was just plain binary files builds from
>>>>>> jenkins,
>>>>> 
>>>>> lurk
>>>>> 
>>>>>> around and see if you can make yourself an ebuild with an overlay.
>>>>>> Also, there's a xen-tools package which has OVMF USE-flag, try
>>>>> 
>>>>> researching
>>>>> 
>>>>>> this.
>>>>>> And i think i saw an user-created portage overlay with the OVMF
>>> 
>>> package
>>> 
>>>>> in
>>>>> 
>>>>>> there.
>>>>>> 
>>>>>> I think plain libvirt and virt-manager should already be in the main
>>>>>> portage tree.
>>>>>> 
>>>>>> 2015-08-19 6:16 GMT+03:00 José Ramón Muñoz Pekkarinen <
>>>>> 
>>>>> koalinux at gmail.com>:
>>>>>>>     Hi,
>>>>>>> 
>>>>>>>    So, I got it right that using OVMF my setup can work reliably?
>>> 
>>> I
>>> 
>>>>> was
>>>>> 
>>>>>>> considering to build it but it seems to be not so straight forward
>>> 
>>> in
>>> 
>>>>>>> Gentoo.
>>>>>>> 
>>>>>>>    BR.
>>>>>>> 
>>>>>>>    José
>>>>>>> 
>>>>>>> On Aug 19, 2015 3:09 AM, "Blank Field" <ihatethisfield at gmail.com>
>>>>> 
>>>>> wrote:
>>>>>>>> Well, that sounds like the first time i've got it working.
>>>>>>>> Sooo, i've managed to make it work back then with just x-vga and
>>>>>>>> qemu.
>>>>>>>> It worked. Sometimes.
>>>>>>>> Sometimes it crashed the host.
>>>>>>>> Sometimes it froze the VM and messed up the GPU.
>>>>>>>> I did a foolish research with no results whatsoever, but i've
>>>>>>>> made
>>>>>>>> one
>>>>>>>> observation - if the firefox is started and it eats a ton of
>>> 
>>> memory,
>>> 
>>>>>>>> i
>>>>>>>> have
>>>>>>>> better chances to run the VM right.
>>>>>>>> However, i've dropped that way and went the OVMF way, avoiding
>>>>>>>> the
>>>>> 
>>>>> VGA.
>>>>> 
>>>>>>>> Check the dmesg, maybe you're more lucky than me with the
>>> 
>>> motherboard
>>> 
>>>>> and
>>>>> 
>>>>>>>> it's just the GPU that freezes. Also, i'd check the temperatures.
>>>>>>>> 
>>>>>>>> 2015-08-19 0:25 GMT+03:00 José Ramón Muñoz <koalinux at gmail.com>:
>>>>>>>>>        Hi,
>>>>>>>>> 
>>>>>>>>>        I'm using and APU a8-7650k, and apart that from time to
>>> 
>>> time
>>> 
>>>>> the
>>>>> 
>>>>>>>>> win7
>>>>>>>>> guest decides to freeze, so many times during boot time, and
>>>>>>>>> ocassionally
>>>>>>>>> during gaming, I'm fairly happy with the performance. The passed
>>>>> 
>>>>> through
>>>>> 
>>>>>>>>> gpu
>>>>>>>>> is a HD5670 and I managed to play games like MGS Ground Zeroes,
>>>>> 
>>>>> Blades
>>>>> 
>>>>>>>>> of
>>>>>>>>> times, and currently DAO: Origins.
>>>>>>>>> 
>>>>>>>>>        Best regards.
>>>>>>>>> 
>>>>>>>>>        José.
>>>>>>>>> 
>>>>>>>>> On Wednesday 19 August 2015 00:09:09 Blank Field wrote:
>>>>>>>>>> Use "Reply All" button. Include the mailing list in the "to:"
>>>>> 
>>>>> field.
>>>>> 
>>>>>>>>>>> I'm currently running an A10-5700 with a discrete Nvidia
>>>>>>>>>>> card,
>>>>>>>>>>> and
>>>>>>>>> 
>>>>>>>>> I've
>>>>>>>>> 
>>>>>>>>>> got a LMDE2 install in which I'm preparing to do an
>>> 
>>> experimental
>>> 
>>>>> W10
>>>>> 
>>>>>>>>> VM.
>>>>>>>>> 
>>>>>>>>>> So, according to your experience, I shouldn't expect much with
>>>>>>>>>> this
>>>>>>>>>> processor, then?
>>>>>>>>>> http://pastebin.com/rEhebfQM
>>>>>>>>>> It will work. But it has taken a year for me to figure out how
>>> 
>>> to
>>> 
>>>>> make
>>>>> 
>>>>>>>>> it
>>>>>>>>> 
>>>>>>>>>> work.
>>>>>>>>>> The pastebin link is my currently working domain xml.
>>>>>>>>>> Two asus HD7750 on an asus F2A55+Athlon X4 750k (Trinity).
>>>>>>>>>> The kernel and module parameters are:
>>>>>>>>>> options kvm-amd npt=1 nested=0
>>>>>>>>>> options kvm ignore_msrs=0 allow_unsafe_assigned_interrupts=0
>>>>>>>>>> options vfio_iommu_type1 disable_hugepages=1
>>>>> 
>>>>> allow_unsafe_interrupts=0
>>>>> 
>>>>>>>>>> CMDLINE:
>>>>>>>>>> nofb pci-stub.ids=1022:780d,1002:683f,1002:aab0
>>>>>>>>>> enable_mtrr_cleanup
>>>>>>>>>> amd_iommu_dump=1 iommu=pt acpi_enforce_resources=lax
>>>>>>>>>> 
>>>>>>>>>> Try doing it with nested=1
>>>>>>>>>> 
>>>>>>>>>> If you will use libvirt, that should work 100%, as i have
>>> 
>>> almost
>>> 
>>>>> the
>>>>> 
>>>>>>>>> same
>>>>>>>>> 
>>>>>>>>>> CPU.
>>>>>>>>>> 
>>>>>>>>>> 2015-08-18 23:57 GMT+03:00 ALG Bass <olorin12 at gmail.com>:
>>>>>>>>>>> Gotcha. So it would be better if I got the i7.
>>>>>>>>>>> I'm currently running an A10-5700 with a discrete Nvidia
>>> 
>>> card,
>>> 
>>>>> and
>>>>> 
>>>>>>>>> I've
>>>>>>>>> 
>>>>>>>>>>> got a LMDE2 install in which I'm preparing to do an
>>> 
>>> experimental
>>> 
>>>>> W10
>>>>> 
>>>>>>>>> VM.
>>>>>>>>> 
>>>>>>>>>>> So, according to your experience, I shouldn't expect much
>>> 
>>> with
>>> 
>>>>> this
>>>>> 
>>>>>>>>>>> processor, then?
>>>>>>>>>>> 
>>>>>>>>>>> On Tue, Aug 18, 2015 at 3:46 PM, Blank Field <
>>>>>>>>> 
>>>>>>>>> ihatethisfield at gmail.com>
>>>>>>>>> 
>>>>>>>>>>> wrote:
>>>>>>>>>>>> Hyperthreading on host means MORE cores which you can
>>> 
>>> commit to
>>> 
>>>>> the
>>>>> 
>>>>>>>>> VM.
>>>>>>>>> 
>>>>>>>>>>>> More cores = more performance.
>>>>>>>>>>>> It is good for you.
>>>>>>>>>>>> For the host it doesn't matter logical or physical. For the
>>> 
>>> VM,
>>> 
>>>>>>>>> you'd
>>>>>>>>> 
>>>>>>>>>>>> want to pin "pairs" of cores, so there would be less CPU
>>> 
>>> cache
>>> 
>>>>>>>>> issues.
>>>>>>>>> 
>>>>>>>>>>>> Like, assign a core and it's sibling instead of two
>>>>>>>>>>>> separate
>>>>> 
>>>>> cores.
>>>>> 
>>>>>>>>>>>> I use AMD Athlon X4 750k which is based off A10-5700, and
>>> 
>>> it's
>>> 
>>>>>>>>> working
>>>>>>>>> 
>>>>>>>>>>>> very unstable.
>>>>>>>>>>>> The only way to get it working - use OVMF without VGA and
>>>>>>>>>>>> do
>>>>>>>>>>>> not
>>>>>>>>>>>> use
>>>>>>>>>>>> hugepages.
>>>>>>>>>>>> That's all.
>>>>>>>>>>>> 
>>>>>>>>>>>> P.S.
>>>>>>>>>>>> Oh well, here we go again.
>>>>>>>>>>>> 
>>>>>>>>>>>> 2015-08-18 22:26 GMT+03:00 ALG Bass <olorin12 at gmail.com>:
>>>>>>>>>>>>> Hi all, new to this list, kvm, and vfio. I've been
>>> 
>>> researching
>>> 
>>>>>>>>> this for
>>>>>>>>> 
>>>>>>>>>>>>> about a week.
>>>>>>>>>>>>> I'm also going to be building a computer in the near
>>> 
>>> future,
>>> 
>>>>>>>>>>>>> so
>>>>>>>>> 
>>>>>>>>> I've got
>>>>>>>>> 
>>>>>>>>>>>>> a quick two part question:
>>>>>>>>>>>>> Does the hyperthreading on i7 series Intel processors make
>>> 
>>> a
>>> 
>>>>>>>>> significant
>>>>>>>>> 
>>>>>>>>>>>>> difference in running Windows in a VM, such that it's a
>>>>> 
>>>>> noticeable
>>>>> 
>>>>>>>>>>>>> increase
>>>>>>>>>>>>> in performance over an i5? And, does anyone here run
>>> 
>>> Windows
>>> 
>>>>> in a
>>>>> 
>>>>>>>>> VM
>>>>>>>>> 
>>>>>>>>>>>>> using
>>>>>>>>>>>>> an AMD A-series APU like the 7700k, and how is the
>>>>>>>>>>>>> performance?
>>>>>>>>>>>>> 
>>>>>>>>>>>>> Thank you!
>>>>>>>>>>>>> 
>>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>>> vfio-users mailing list
>>>>>>>>>>>>> vfio-users at redhat.com
>>>>>>>>>>>>> https://www.redhat.com/mailman/listinfo/vfio-users
> 
> 
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