vpp load balance issue for gstvaapi and ffmpeg-vaapi.

test platform: ICL
commit id:
```
commit 79634e7db3604d6a4226c32a13c7135c0aded0d0 (HEAD -> master, origin/master, origin/HEAD)
Author: ChenJasonK
Date: Mon Jan 6 19:06:15 2020 +0800

[VP] Update Wa for 128/256 mode setting

Update Wa for 128/256 mode setting for compression

Change-Id: I7e627d2858a35bf52275d2d390788bd2db36e12a

```
steps:
1. run multi processes decode + vpp like this
```
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! vaapipostproc scale-method=1 ! "video/x-raw(memory:DMABuf),format=RGBA,width=300,height=300" ! fpsdisplaysink video-sink=fakesink sync=false &
```

2. check the fps, some channels will get 100+ fps, some channel only gets 1~2 fps at the start.

this never happened for decode only. case like this

```
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &
time gst-launch-1.0 -v filesrc location=/tmp/1080P.264 ! h264parse ! vaapih264dec ! "video/x-raw(memory:DMABuf)" ! fpsdisplaysink video-sink=fakesink sync=false &

```

3. if you use gdb to trace one channel. You will see it blocked at DdiMediaDecode::AllocBsBuffer.
please help check why
```
#0 0x00007ffff7be667b in ioctl () at ../sysdeps/unix/syscall-template.S:78
#1 0x00007ffff49b7638 in mosdrmIoctl(int, unsigned long, void*) (fd=8, request=1074553951, arg=0x7ffff16e5f84) at /home/thomas/projects/media-driver/media_driver/linux/common/os/i915/xf86drm.c:171
#2 0x00007ffff49b107c in mos_gem_bo_start_gtt_access(mos_linux_bo*, int) (write_enable=1, bo=0x7fffe8374f40) at /home/thomas/projects/media-driver/media_driver/linux/common/os/i915/mos_bufmgr.c:2052
#3 0x00007ffff49b107c in mos_gem_bo_wait_rendering(mos_linux_bo*) (bo=0x7fffe8374f40) at /home/thomas/projects/media-driver/media_driver/linux/common/os/i915/mos_bufmgr.c:1973
#4 0x00007ffff496e681 in DdiMediaDecode::AllocBsBuffer(_DDI_CODEC_COM_BUFFER_MGR*, _DDI_MEDIA_BUFFER*) (this=0x7fffe80782f0, bufMgr=0x7fffe8078ba8, buf=0x7fffe862f8b0) at /home/thomas/projects/media-driver/media_driver/linux/common/codec/ddi/media_ddi_decode_base.cpp:514
#5 0x00007ffff496ee28 in DdiMediaDecode::CreateBuffer(VABufferType, unsigned int, unsigned int, void*, unsigned int*) (this=0x7fffe80782f0, type=VASliceDataBufferType, size=87, numElements=1, data=0x7fffe838c7a2, bufId=0x7ffff16e6144)
at /home/thomas/projects/media-driver/media_driver/linux/common/codec/ddi/media_ddi_decode_base.cpp:876
#6 0x00007ffff499698f in DdiMedia_CreateBuffer(VADriverContextP, VAContextID, VABufferType, uint32_t, uint32_t, void*, VABufferID*) (ctx=0x55555575a000, context=268435456, type=VASliceDataBufferType, size=87, num_elements=1, data=0x7fffe838c7a2, bufId=0x7ffff16e6144)
at /home/thomas/projects/media-driver/media_driver/linux/common/ddi/media_libva.cpp:2720
#7 0x00007ffff6eb7147 in vaCreateBuffer (dpy=dpy@entry=0x5555557278e0, context=268435456, type=type@entry=VASliceDataBufferType, size=87, num_elements=num_elements@entry=1, data=0x7fffe838c7a2, buf_id=0x7ffff16e6144) at va.c:1371
#8 0x00007ffff6f33f36 in vaapi_create_n_elements_buffer (dpy=0x5555557278e0, ctx=, type=type@entry=5, size=, buf=, buf_id_ptr=buf_id_ptr@entry=0x7fffe8028a2c, mapped_data=0x0, num_elements=1) at ../gst-libs/gst/vaapi/gstvaapiutils.c:182
#9 0x00007ffff6f33fdf in vaapi_create_buffer (dpy=, ctx=, type=type@entry=5, size=, buf=, buf_id_ptr=buf_id_ptr@entry=0x7fffe8028a2c, mapped_data=0x0) at ../gst-libs/gst/vaapi/gstvaapiutils.c:169
#10 0x00007ffff6f22746 in gst_vaapi_slice_create (slice=0x7fffe8028a10, args=0x7ffff16e61c0) at ../gst-libs/gst/vaapi/gstvaapidecoder_objects.c:454
#11 0x00007ffff6f716f2 in gst_vaapi_codec_object_create (args=0x7ffff16e61c0, object=0x7fffe8028a10) at ../gst-libs/gst/vaapi/gstvaapicodec_objects.c:62
#12 0x00007ffff6f716f2 in gst_vaapi_codec_object_new (object_class=object_class@entry=0x7ffff6fbf150 , codec=codec@entry=0x7fffe802ed20, param=param@entry=0x0, param_size=param_size@entry=3128, data=0x7fffe838c7a2, data_size=87, flags=0) at ../gst-libs/gst/vaapi/gstvaapicodec_objects.c:92
#13 0x00007ffff6f22c50 in gst_vaapi_slice_new (decoder=decoder@entry=0x7fffe802ed20, param=param@entry=0x0, param_size=param_size@entry=3128, data=, data_size=) at ../gst-libs/gst/vaapi/gstvaapidecoder_objects.c:479
#14 0x00007ffff6f163d1 in decode_slice (unit=0x7fffe85a7590, unit=0x7fffe85a7590, decoder=0x7fffe802ed20) at ../gst-libs/gst/vaapi/gstvaapidecoder_h264.c:4257
#15 0x00007ffff6f163d1 in decode_unit (unit=0x7fffe85a7590, decoder=0x7fffe802ed20) at ../gst-libs/gst/vaapi/gstvaapidecoder_h264.c:4312
#16 0x00007ffff6f163d1 in gst_vaapi_decoder_h264_decode (base_decoder=0x7fffe802ed20, unit=0x7fffe85a7590) at ../gst-libs/gst/vaapi/gstvaapidecoder_h264.c:4701
#17 0x00007ffff6f0d5aa in do_decode_units (decoder=decoder@entry=0x7fffe802ed20, units=0x7fffe801ccf0) at ../gst-libs/gst/vaapi/gstvaapidecoder.c:226
#18 0x00007ffff6f0f0df in do_decode_1 (frame=, decoder=0x7fffe802ed20) at ../gst-libs/gst/vaapi/gstvaapidecoder.c:254
#19 0x00007ffff6f0f0df in do_decode (base_frame=0x555555716c10, decoder=0x7fffe802ed20) at ../gst-libs/gst/vaapi/gstvaapidecoder.c:287
#20 0x00007ffff6f0f0df in gst_vaapi_decoder_decode (decoder=0x7fffe802ed20, frame=frame@entry=0x555555716c10) at ../gst-libs/gst/vaapi/gstvaapidecoder.c:1049
#21 0x00007ffff6eefa18 in gst_vaapidecode_handle_frame (vdec=0x5555556f0670, frame=0x555555716c10) at ../gst/vaapi/gstvaapidecode.c:719
#22 0x00007ffff7153111 in gst_video_decoder_decode_frame (decoder=decoder@entry=0x5555556f0670, frame=0x555555716c10) at ../gst-libs/gst/video/gstvideodecoder.c:3473
#23 0x00007ffff715c091 in gst_video_decoder_have_frame (decoder=decoder@entry=0x5555556f0670) at ../gst-libs/gst/video/gstvideodecoder.c:3405
#24 0x00007ffff6eef4fa in gst_vaapidecode_parse_frame (at_eos=0, adapter=0x5555556e3360, frame=0x555555716c10, vdec=0x5555556f0670) at ../gst/vaapi/gstvaapidecode.c:1159
#25 0x00007ffff6eef4fa in gst_vaapidecode_parse (vdec=0x5555556f0670, frame=0x555555716c10, adapter=0x5555556e3360, at_eos=0) at ../gst/vaapi/gstvaapidecode.c:1196
#26 0x00007ffff7155703 in gst_video_decoder_parse_available (dec=dec@entry=0x5555556f0670, at_eos=at_eos@entry=0, new_buffer=0, new_buffer@entry=1) at ../gst-libs/gst/video/gstvideodecoder.c:958
#27 0x00007ffff715843c in gst_video_decoder_chain_forward (decoder=decoder@entry=0x5555556f0670, buf=buf@entry=0x7fffe828b120, at_eos=at_eos@entry=0) at ../gst-libs/gst/video/gstvideodecoder.c:2204
#28 0x00007ffff7158a81 in gst_video_decoder_chain (pad=, parent=, buf=0x7fffe828b120) at ../gst-libs/gst/video/gstvideodecoder.c:2503
#29 0x00007ffff7f0a1a3 in gst_pad_chain_data_unchecked (data=0x7fffe828b120, type=4112, pad=0x5555556d6800) at ../gst/gstpad.c:4399
#30 0x00007ffff7f0a1a3 in gst_pad_push_data (pad=pad@entry=0x5555556d65b0, type=type@entry=4112, data=data@entry=0x7fffe828b120) at ../gst/gstpad.c:4655
#31 0x00007ffff7f129f3 in gst_pad_push (pad=0x5555556d65b0, buffer=buffer@entry=0x7fffe828b120) at ../gst/gstpad.c:4774
#32 0x00007ffff72bf588 in gst_base_parse_push_frame (parse=parse@entry=0x5555556d9a80, frame=frame@entry=0x7fffe80718a0) at ../libs/gst/base/gstbaseparse.c:2625
#33 0x00007ffff72c222b in gst_base_parse_handle_and_push_frame (frame=0x7fffe80718a0, parse=0x5555556d9a80) at ../libs/gst/base/gstbaseparse.c:2439
#34 0x00007ffff72c222b in gst_base_parse_finish_frame (parse=parse@entry=0x5555556d9a80, frame=frame@entry=0x7fffe80718a0, size=size@entry=120) at ../libs/gst/base/gstbaseparse.c:2783
#35 0x00007ffff726d444 in gst_h264_parse_handle_frame (parse=0x5555556d9a80, frame=0x7fffe80718a0, skipsize=0x7ffff16e6d8c) at ../gst/videoparsers/gsth264parse.c:1479
#36 0x00007ffff72ba325 in gst_base_parse_handle_buffer (parse=parse@entry=0x5555556d9a80, buffer=, skip=skip@entry=0x7ffff16e6d8c, flushed=flushed@entry=0x7ffff16e6d88) at ../libs/gst/base/gstbaseparse.c:2247
#37 0x00007ffff72baaca in gst_base_parse_scan_frame (parse=parse@entry=0x5555556d9a80, klass=) at ../libs/gst/base/gstbaseparse.c:3532
#38 0x00007ffff72bde83 in gst_base_parse_loop (pad=) at ../libs/gst/base/gstbaseparse.c:3611
#39 0x00007ffff7f40ab9 in gst_task_func (task=0x5555556e3710) at ../gst/gsttask.c:328
#40 0x00007ffff7dbb854 in () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#41 0x00007ffff7dbb111 in () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#42 0x00007ffff7cc9669 in start_thread (arg=) at pthread_create.c:479
#43 0x00007ffff7bf1323 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

```