I'm just doing a simple cloner fill on a volume via Dynamics body tags.
Just a sphere, filled with cubes. Since it uses Dynamics, it takes several frames for the cloned objects to 'settle' the way I want them - so of course, I render out frame 5 or so.
Two probs - could use an expert opinion.
When I render view, on frame 5, for a preview, the render starts immediately - just a few seconds of prep. Everything looks the way I like it. Great. So time to render to picture viewer. Leaving the settings exactly as-is, couple weird things happen:
1) It gets stuck on 'Preparing...' as the memory racks up to gobble all 16GB. I think I can get it to go if I lower the clone count, but:
2) Even when I do lower the clone count, as a test - it's almost like the dynamics for the viewport-rendered frame 5 doesn't even come close to what I'm seeing with the picture-viewer-rendered frame 5.
I didn't think it mattered which render method was used, since they simply pull from the same render settings.
I don't know why it's taking so long. If you could post the file I'd be happy to take a look.
As far as the render view not matching the dynamics of the editor view, it's always a good idea to cache the dynamics before rendering. That will also speed up the render to some extent because if you don't cache, all of the preceding frames still have to be calculated by the render engine.