[vfio-users] Hyperthreading and kvm

[Blank Field]

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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