Recording performance

  • JReykdal

    OS: Suse 11.4

    HP ML150 G6
    1x Xeon 5504 @2000MHz (4 core, no HT)
    RAM 10GB
    system on SSD
    /video on RAID-0 (hdparm -tT gives about 180MB/s)
    Atomix LT card with latest driver and firmware

    Is this system too slow to record 2 HD streams at the same time? I've tried both DVCPro-HD and dnxhd with no success.

    command line:

     sudo nice --10 ./dvs_sdi -c 2 -mode 1920x1080i25 -f YUV422 -s None -mc 0 -tt SYS 
    I put the secondary buffer to None. Was that wrong? 
    I've tried to increase shmmax to 2048 and put -m 2048 to the command line.
    Recorder processes run up to 200% in top (cpu hovering around 99%)
    Soon after starting the recording I start to get:
    [code14:21:04.578 input1 index 0 EncodeFrameBuffer contains 250 frames (1 coded)

    and then:

    MtEncoder missed frame   2593!
    14:21:04.872 input1 index 0 EncodeFrameBuffer contains 253 frames (4 coded)
    input1 index 0 Coded frame 2593 has error!
    14:21:04.897 input1 index 0 EncodeFrameBuffer contains 252 frames (2 coded)

    And finally it segfaults.

    I've tried running it headless from the command line to exclude X but that seems to have no effect.



  • John Fletcher
    John Fletcher

    Yes, maybe too slow.  DVCPRO-HD is a lot easier to code than DNxHD.  Did you try just one channel of video?  You can see individual core usage with gkrellm - check whether they are peaking to full scale.

  • JReykdal

    One channel seems to work fine.

    Now has it been recording for 30 minutes or so with each core around 75%. When I started I was using a terrible upscaled signal from a bad source. Maybe that also is working against it.

    Guess this is what happens when you're not a part of the buying process :D