On 2/9/19 6:23 pm, Brad Campbell wrote:
Here is the holdup :
11725@1567416625.003504:qxl_ring_command_check 0 native
11725@1567416625.102653:qxl_io_write 0 native addr=0 (QXL_IO_NOTIFY_CMD)
val=0 size=1 async=0
~100ms delay prior to each logged QXL_IO_NOTIFY_CMD on the AMD box which
explains the performance difference. Now I just need to figure out if
that lies in the guest, the guest QXL driver, QEMU or SPICE and why it
exhibits on the AMD box and not the i7.
To get to this point, I recompiled the kernel on the i7 box with both
AMD and Intel KVM modules. Once that was running I cloned the drive and
put it in the AMD box, so the OS, software stack and all dependencies
are identical.
Reacp :
I have a machine with a Windows 7 VM which is running on an i7-3770. This
works perfectly.
Clone the disk and put it in a new(ish) AMD Ryzen 1500x machine and the
display output using qxl/spice is now limited to ~5-7fps.
I originally cloned the entire machine to keep the software versions
identical.
To simplify debugging and reproduction I'm now using :
- An identical SPICE version to that on the i7.
- A fresh 64 bit Windows 7 VM.
- The D2D benchmark from Crystalmark 2004R7.
The machine is booted with :
qemu -enable-kvm \
-m 8192\
-rtc base=localtime\
-vga qxl\
-device qxl\
-global qxl-vga.guestdebug=3\
-global qxl-vga.cmdlog=1\
-global qxl-vga.vram_size=65536\
-global qxl.vram_size=65536\
-global qxl-vga.ram_size=65536\
-global qxl.ram_size=65536\
-net nic,model=virtio\
-net tap,ifname=tap0,script=/etc/qemu-ifup,vhost=on\
-usbdevice tablet\
-spice port=5930,disable-ticketing\
-device virtio-serial\
-chardev spicevmc,id=vdagent,name=vdagent\
-device virtserialport,chardev=vdagent,name=com.redhat.spice.0\
-smp 3,maxcpus=3,cores=3,threads=1,sockets=1\
-cpu qemu64,hv_relaxed,hv_spinlocks=0x1fff,hv_vapic,hv_time \