Announcement

Collapse
No announcement yet.

DR bucket behaviour

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • DR bucket behaviour

    Hi,
    I recently set up a render farm for us consisting of (total) 3 workstations and 3 render nodes. Now when I got DR up and running everything seemed to work fine, but I noticed one thing:
    When rendering with all available machines, it often happens that the buckets of one or several machines get rendered correctly, but not immediately getting assigned "new buckets" if that makes sense. It seems they render their assigned buckets, then have a little delay of a couple of seconds, then get assigned new buckets, and not how I expected they render one bucket, and as soon as they are finished with one bucket, directly continue rendering the next one.

    Could this be some kind of overhead issue? Is it a known issue? Its a relatively simple image, but large in pixel dimensions (10k), also its writing a vrimg on the fly onto the network. I can provide a scene, although I don't think it would make much sense.
    Software:
    Windows 7 Ultimate x64 SP1
    3ds Max 2016 SP4
    V-Ray Adv 3.60.04


    Hardware:
    Intel Core i7-4930K @ 3.40 GHz
    NVIDIA GeForce GTX 780 (4096MB RAM)
    64GB RAM


    DxDiag

  • #2
    Hi,

    It looks like a network issue, but can't be sure about that. What is the speed of your local network?
    Is it possible to run some tests with bigger bucket size and smaller resolution ? Maybe without writing the render into a file ?
    And this is Max 2016 like shown in your signature ?

    Update: Do you have any proxy file or displacement geo in this scene?
    Tashko Zashev | chaos.com
    Chaos Support Representative | contact us

    Comment


    • #3
      Hi,

      1) The speed of our network is 1 GBit, via a HP 1820-48G Switch.
      2) I can run some tests with the changed parameters you mentioned. Will do and report back.
      3) Yes, it is 3ds max 2016 with VRay 3.60.03
      4) The only "special" stuff in the scene is a simple multiscatter. It's just a test scene, with a teapot, textured with a texture on the network, and multiscattered boxes on top of the teapot. Nothing else.

      I hope the issue can be solves without disabling the vrimg write, since I would love to have it to be able to resume a rendering.
      Software:
      Windows 7 Ultimate x64 SP1
      3ds Max 2016 SP4
      V-Ray Adv 3.60.04


      Hardware:
      Intel Core i7-4930K @ 3.40 GHz
      NVIDIA GeForce GTX 780 (4096MB RAM)
      64GB RAM


      DxDiag

      Comment


      • #4
        Alright, I made some more tests. As for your edit: No there's no proxies or displacement involved. It is just a teapot, a domelight and a groundplane.

        Reducing output resolution to 5k and increasing bucket size from 32 to 128 did not make any difference. Yet disabling file save altogether did make a difference, yet the behaviour is still present, although to a much smaller degree.
        I monitored network load and it averaged around 20% network load on the 1GBit connection, with bottoms of 5% and short peaks of 80%. Here's a video of the behaviour along with network load:

        With file saving:
        --deleted--
        The points where it happens are evident. After gradually losing buckets, they all jump back in at 1:04

        Without file saving:
        --deleted--
        Way less of the behaviour, yet still there, for example at 0:50 where the blob of new buckets appear.
        Last edited by Art48; 04-04-2018, 02:44 AM. Reason: Deleting videos
        Software:
        Windows 7 Ultimate x64 SP1
        3ds Max 2016 SP4
        V-Ray Adv 3.60.04


        Hardware:
        Intel Core i7-4930K @ 3.40 GHz
        NVIDIA GeForce GTX 780 (4096MB RAM)
        64GB RAM


        DxDiag

        Comment


        • #5
          Originally posted by Art48 View Post
          ... also its writing a vrimg on the fly onto the network. ....
          Hello,

          What is the network server? Is it a dedicated NAS or, Windows or Linux machine?
          Does the problem still occur if you save the .vrimg file locally?
          V-Ray for 3ds Max developer

          Comment


          • #6
            Hi,

            The network server is a DiskStation DS1815+ with 8x WD-WCC4E0023240 HDDs (ext4) running as RAID-5. I will test writing the image locally and report back.
            Software:
            Windows 7 Ultimate x64 SP1
            3ds Max 2016 SP4
            V-Ray Adv 3.60.04


            Hardware:
            Intel Core i7-4930K @ 3.40 GHz
            NVIDIA GeForce GTX 780 (4096MB RAM)
            64GB RAM


            DxDiag

            Comment


            • #7
              No changes when saving to the local C: drive of the machine I'm starting the rendering from.
              --deleted--
              Last edited by Art48; 04-04-2018, 02:44 AM. Reason: Deleting videos
              Software:
              Windows 7 Ultimate x64 SP1
              3ds Max 2016 SP4
              V-Ray Adv 3.60.04


              Hardware:
              Intel Core i7-4930K @ 3.40 GHz
              NVIDIA GeForce GTX 780 (4096MB RAM)
              64GB RAM


              DxDiag

              Comment


              • #8
                Hi again,

                Tested this one more time and I'm getting the same behavior for the DR slave buckets in a little bit higher resolution. Here is what happens:
                https://ftp.chaosgroup.com/support/s...4_09-08-23.gif
                There is a big difference when the file is not saved to the disk during the rendering process so we'll look into it and try to make some optimizations.
                Tashko Zashev | chaos.com
                Chaos Support Representative | contact us

                Comment


                • #9
                  Great to hear, hopefully you can make some optimizations, in the end you can have another changelog entry stating "Up to 20% faster rendering speed under certain conditions" . Just kidding - thanks for the confirmation!
                  Software:
                  Windows 7 Ultimate x64 SP1
                  3ds Max 2016 SP4
                  V-Ray Adv 3.60.04


                  Hardware:
                  Intel Core i7-4930K @ 3.40 GHz
                  NVIDIA GeForce GTX 780 (4096MB RAM)
                  64GB RAM


                  DxDiag

                  Comment


                  • #10
                    Also if you don't need to see them anymore, I'd take down the youtube videos. Feel free to download them for reference, and/or tell me when it's fine to take them down.
                    Software:
                    Windows 7 Ultimate x64 SP1
                    3ds Max 2016 SP4
                    V-Ray Adv 3.60.04


                    Hardware:
                    Intel Core i7-4930K @ 3.40 GHz
                    NVIDIA GeForce GTX 780 (4096MB RAM)
                    64GB RAM


                    DxDiag

                    Comment


                    • #11
                      Originally posted by Art48 View Post
                      Also if you don't need to see them anymore, I'd take down the youtube videos. Feel free to download them for reference, and/or tell me when it's fine to take them down.
                      It's OK to remove them now. Thanks !
                      Tashko Zashev | chaos.com
                      Chaos Support Representative | contact us

                      Comment

                      Working...
                      X