[Jetson-TK1] Slow web camera

I have a Microsoft LiveCam which I have been using together with the “v4l” library to capture raw video in video encoding experiments. The webcamera is simply connected directly to the Jetson on the USB port. However, reading from the web camera is now unbelieveably slow (varies between 10-80 ms for 352x288 pixel frames). I’m using DMA buffers (http://linuxtv.org/downloads/v4l-dvb-apis/vidioc-qbuf.html) to read the frames. (This previously took little more than 1 ms per frame).

Does anyone have any thoughts as to why this happens? I have done nothing with the board’s hardware / software configuration. It just sort of happened…

What release are you using?

I also recommend maximising CPU, GPU and EMC clocks when doing any performance measurements: