[Spice-devel] Testing playback of flash videos at 1920x1080 part2

[Hans de Goede]

Hi all,

Given the feedback on my previous tests I've been re-running them. Changes:
-now include bandwidth measurement
-now include guest cpu usage measurements
-qemu started with -host cpu to enable sse2 - 4, etc in the vm.
-both uni processor and duo core virtual machine results
-I've found a bug in the 2.6.35 kernel causing very poor performance
  with my ati x1950 pro, downgraded to 2.6.34 to take this out of the
  picture (much lower xorg cpu usage)

The conclusion is unchanged though the biggest bottleneck is the guest
cpu. It is different then I thought though, it seems that flash is
using scaled bitmap blitting, so the stretching of video to
1920x1080 is not a problem. The software decoding is. Flash videos encoded
in in resolutions up to 480p work fine. Once you try to play 720p
videos fullscreen things start falling apart. I have not tried 1080p
videos.

With uni processor vm's the 720p problem clearly is guest cpu related,
with duo core processor vm's this is less obvious, but likely still
the cause. Going beyond 2 cores does not work / help with XP. Still waiting
for my msdn subscription to be able to build a vm image with windows 7.

Here are the results:

-server: F-14 with kernel 2.6.34.6-54.fc13.x86_64, see bug rhbz#630955
  spice + qemu 0.4, from:
  git clone git://git.engineering.redhat.com/users/ehabkost/qemu-kvm-rhel6.git --branch rhel6/master
  git clone git://git.engineering.redhat.com/users/ulublin/spice.git
  AMD Phenom(tm) II X4 945 Processor
  4G RAM
  Guest: 1 "core" cpu, 2G RAM, windows XP + ie8 + flash 10.1 with spice display driver
         and agent.

  -client: on same machine, Radeon X1950 Pro, fullscreen to 1920x1080
   - 480 p 4:3 youtube video:
    qemu cpu load: 110%
    xorg cpu load:  20%
    spicec cpu ld:  25%
    lo bandwidth:    6mbit
    guest cpu load: 80%
    frame drop (*):  0

   - 480 p 16:9 youtube video:
    qemu cpu load: 120%
    xorg cpu load:  20%
    spicec cpu ld:  25%
    lo bandwidth:    6mbit
    guest cpu load: 80%
    frame drop: looks smooth (no video info)

   - 720 p 16:9 youtube video:
    qemu cpu load:  130%
    xorg cpu load:   20%
    spicec cpu ld:   25%
    lo bandwidth:    8-16mbit
    guest cpu load: 100%
    frame drop: seems to drop a few frames every sec. (no video info)

  Guest: 2 "core" cpu, 2G RAM, windows XP + ie8 + flash 10.1 with spice display driver
         and agent.

   - 360 p 16:9 youtube video:
    qemu cpu load: 130%
    xorg cpu load:  20%
    spicec cpu ld:  25%
    lo bandwidth:   10mbit
    guest cpu load: 60 + 20%
    frame drop (*): 0

   - 480 p 4:3 youtube video:
    qemu cpu load: 130%
    xorg cpu load:  20%
    spicec cpu ld:  25%
    lo bandwidth:    6mbit
    guest cpu load: 60 + 20%
    frame drop (*): 0

   - 480 p 16:9 youtube video:
    qemu cpu load: 140%
    xorg cpu load:  20%
    spicec cpu ld:  25%
    lo bandwidth:    6mbit
    guest cpu load:
    frame drop: looks smooth (no video info)

   - 720 p 16:9 youtube video:
    qemu cpu load:  165%
    xorg cpu load:  10%
    spicec cpu ld:  30%
    lo bandwidth:   9 - 16mbit
    guest cpu load: 90 + 50%
    frame drop:     50% (every other frame or so) (no video info)


-server: F-14 with kernel 2.6.34.6-54.fc13.x86_64, see bug rhbz#630955
  spice + qemu-kvm-spice master
  AMD Phenom(tm) II X4 945 Processor
  4G RAM

  Guest: 2 "core" cpu, 2G RAM, windows XP + ie8 + flash 10.1 with spice display driver
         and agent.

   - 360 p 16:9 youtube video:
    qemu cpu load: 130%
    xorg cpu load:  20%
    spicec cpu ld:  25%
    lo bandwidth:   7mbit
    guest cpu load: 60 + 20%
    frame drop (*): 0

   - 480 p 4:3 youtube video:
    qemu cpu load: 120%
    xorg cpu load:  15%
    spicec cpu ld:  20%
    lo bandwidth:    4mbit
    guest cpu load: 60 + 20%
    frame drop (*): 0

   - 480 p 16:9 youtube video:
    qemu cpu load: 130%
    xorg cpu load:  15%
    spicec cpu ld:  20%
    lo bandwidth:    4mbit
    guest cpu load: 60 + 35%
    frame drop: looks smooth (no video info)

   - 720 p 16:9 youtube video:
    qemu cpu load:  145%
    xorg cpu load:  10%
    spicec cpu ld:  25%
    lo bandwidth:   12mbit
    guest cpu load: 90 + 50%
    frame drop:     50% (every other frame or so) (no video info)


*) When not moving mouse, etc.


###

Giving the Guest 2 cpu's to try and solve the cpu starvation problem
results in the flash player inside the guest sometimes hanging
until it has completely downloaded the movie.

Locking problem? I've seen this only once but we have reports of 5 second
or longer delays when starting flash video.

Once that is done flash player does use the second cpu,
but the resulting playback is still dropping frames.


Regards,

Hans