3 Replies Latest reply on May 7, 2009 1:31 AM by Mylenium

    fields rendering with multithread

    sylvaimz

      Hello,

       

      When i try to render a big comp in interlaced mode with multithreading enable,

      the process start normaly but after a few frames, all the child say 0% of cpu and the main apps say about 140-200% of cpu.

       

      If i try to render the same comp in progressive mode, all the cores are use...

       

      My hardware is a Mac Pro 2x2,93 (nehalem) with 24g.

       

       

      thanks.

        • 1. Re: fields rendering with multithread
          Mylenium Most Valuable Participant

          Please provide more info. What effects are you using? What is the size of the comp? To what format are you rendering? Render settings? Motion blur? The mp rendering going down almost certainly means there is a temporal dependency that makes it necessary to know what the next frame will be like before generating the fields. even simple time-remapping can do that...

           

          Mylenium

          • 2. Re: fields rendering with multithread
            sylvaimz Level 1

            Excuse me for low details...

             

            I'm using CS4.

            My comp use a lot of Card Wipe effect, Color Fill, and text layer updated by a script... i don't use Motion blur.

            I have an expression that check a text layer value ( a number ) to update the color of a color fill effect; this about 108 times multiply by 5... :b

             

             

            The size of the comps is 720x576 (1,07) PAL4/3...

            For rendering, i'm using Quicktime Animation codec Upper field first.

            I don't have time remapping in my comp...

             

            When i try to render in Quicktime Animation without fields, no problem: all the cores are use...

             

             

            I don't understand any more...

            • 3. Re: fields rendering with multithread
              Mylenium Most Valuable Participant

              Mmmh, I would guess that it's something with how the expression evaluates. If it's tied to time instad of discrete frames, rendering with fields would force it to calculate for the inbetween times. Depending on the complexity, this could slow down things considerably and make it appear as if the other instances had nothing to do. Hard to tell. Could you post the project for analysis?

               

              Mylenium