This can't be right - 14% CPU utilization render

Terje wrote on 4/16/2013, 5:42 PM

So, I went out and bought me a new work station. Alienware thing with an Intel Intel Core i7-3930K CPU, 16G of RAM and a GTX-660 video card. Just plugged it in and put Vegas on it. Oh, man, I am disappointed.

This thing renders twice as fast as my old AMD quad core thing, but the AMD is ancient, so the four cores are nowhere near at 75% of the hexacore. Igt should render at at least 3x or better. Geekbench clocks my AMD at 5000 or something, and the Alienware at above 20 000.

I did not expect Vegas to utilize my GPU - I don't think the Kepler architecture is supported yet. I did expect it to be able to utilize my CPU though. A little bit.

Simple project with some quicktime movs with transparency as overlays, some text, a few images, a couple of AVCHD video clips. Render to AVCHD. The CPU Utilization never goes above 15%. On my AMD it never goes above about 40%, so I am not only disappointed with the new box, the old one wasn't being taxed either.

This can't be right though. Why on earth would Vegas only use 14% CPU for rendering? I have (well, actually, Vegas did) set render threads to 16.

Is there anything I can do to make Vegas use my CPU?

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Comments

rmack350 wrote on 4/19/2013, 2:15 PM

Vegas' timeline playback definitely has a lot more overhead than, for example, its trimmer playback. There's a lot going on there that doesn't happen in a dedicated player that's "merely" playing the file.

The relative load of CPUs never strikes me as the most important metric. The direct measure is render time. Is it faster? CPU load is an indirect measure and it implies that the render could be even faster if the CPU could be kept busy.

And since we're just talking about a percentage measure it's all relative. In each case the CPU gets a bucket of work/second and the faster CPU dispatches it without breaking a sweat. Maybe this is Vegas's doing, maybe it's some sort of inefficient round-tripping, maybe it's disk throughput.

Hulk wrote on 4/19/2013, 3:17 PM

It is somewhat frustrating that even at version 12 Vegas still relies heavily on single threaded instruction efficiency. Unfortunately the x86 -64 architecture is pretty much topped out as far as IPC goes. And clockspeed as well for that matter. Perhaps AVX is our last hope...

The fact that you can't buy lots of core and have Vegas able to "floor the cores" is disappointing. I mean we're not talking about writing super difficult to multi-thread game code.