BufferScan in Nsight Systems

Autonomous Machines Jetson & Embedded Systems Jetson AGX Xavier
1

Hello,

I am using Nsight Systems to profile an application on the Jetson Xavier. I am using gstreamer, via OpenCV, to render a video stream from a camera using this call to set up the renderer:

cv::VideoWriter writer("appsrc ! videoconvert ! video/x-raw, format=BGRx " \
                "! nvdrmvideosink sync=false conn-id=0 set-mode=1",
                0, (double)FRAME_RATE, cv::Size(1920,1080));

When I profile the application, there is a line at the bottom of the Timeline View that says “BufferScan (0:0)”. Each time a frame renders, I see a bar there with information regarding a handle ID, and times referring to queued, posted, and activated. What do each of these things refer to, and where can I find more information or some documentation?

Thanks,
Alex

2

Hi,

Nsight system’s document can be found here:
https://docs.nvidia.com/nsight-systems/

Thanks.

3

Thanks for the reply, however I asked the question to the forum because I wasn’t able to find what I needed in the documentation. Can you please point to where in the documentation I can find the answer?

4

Hi,

Sorry to keep you waiting.
Could you share a screen capture of the information you are talking about with us?

Thanks.

5

Hi, I can’t figure out how to attach an image. However, I have figured out that it is related to drmModeSetPlane. The call time of this function is approximately the same as the “queued” and “posted” times, and then the function blocks until the next vblank interval, which is the “activated” time.

6

Hi,

Thanks for sharing this to us.
The information may come from backend frameworks, which won’t be listed in the Nsight System document.

Thanks.