Slow rendering but no PC resources at 100%

[Mark MacLean]

I am new at Vegas and just built a PC for the purpose. The PC is an AMD Phenom X6 (6 cores), 4G ram, ASUS M4A88TD-V (integrated video) MB. I have two 1T SATA drives, with source video on one disk outputting to the other. The OS is Windows 7 64 bit, with Vegas 10.

I am taking some video from my Sony camcorder and recoding it, basically just concatenating the files together as a first run, will use some fancier tools later as I get better. I am outputing to AVCHD, with the intention of playing it on the PS3.

What surprises me is that when I look at the resource utilization CPU is only at 30%, and disk utilization is also very low.Memory is at about 50%.... so where is the bottleneck? I was expecting the CPU to be at 100%. Obviously something is slowing it down but I can't see what.

I don't mind adding memory or a video card if I need to but don't want to just shoot in the dark. Any suggestions would be appreciated. I have attached a screen capture with task manager and resource manager running... the values shown are typical for the project.

[Craig Longman]

Under Options->Preferences in the Video tab, how many threads are set as the max for rendering?

You mention this just being a basic concatenation of clips, but if you have any effect on that has a little yellow dot beside it, that effect cannot be run in parallel and will slow down the render.

Finally, there does appear to be a whole heck of a lot of clips, maybe there is some overhead in Vegas wrt opening each one, or handling the transitions that introduces some sort of serialization.

Nice machine BTW, sounds similar to what I want to build, except I'd put an ATI 58xx card in there.
How long does the render take and how long is the final cut?

[Craig Longman]

And one other thing, even just using MS-Paint to convert that image to JPEG instead of BMP would result in a file at least 1/10 as big, if not closer to 1/20. BMPs are horrid things to pass around =)

[Jeff Harper]

It is normal to not get 100% utilization of your CPU. If Vegas was using 100% of your CPU, then the computer would have no resources left to run on.

Your question is common. It's not how much of the processor is used, but how fast the processor is, that makes the difference.

[Roger Shealy]

Mark,

I just built a new machine and am experiencing the same issues. I will look at some of the advice in the thread. One thing I did not, however, is that on a simple sample clip, 1.3 minutes of HD .mov the render time to 1080-30P was 5:00 when the render setting was set to automatic or GPU and 3:00 when set to CPU. The option appears at the bottom of the render window.

I'm not sure how a complicated project changes the results, but this is a pretty profound difference. I'm trying to find links to anyone that has vetted the variables for optimizing renders on Vegas 10 (or even V9). I've found SSD versus SataII, versus SataIII didn't have any appreciable impact on this simple project. CPU when rendered on "auto" or "GPU" ran only 4 of 8 cores at about 17-20%. When "CPU" selected, CPU ran at about 50-70% and render time decreased 40%!

(I'm running a i7-950, 470GTX, 12GB DDR 1600 RAM, OCZ 120GB SSD for OS/programs and two 6GB SataIII's for source and target files)

[Jeff Harper]

Mark, why do you expect your PC to run at 100% for Vegas? Where do you get that expecation? It is not printed or written anywhere. If it did run at 100% it would indicate the processor was being overworked, not that it is running well. 40%-60% is normal. But it varies a lot depending on the processor.

The numbers you should be looking at are how long it takes to render video, which you do not mention. You are leaving out the most important piece of information.

I render a 90 minute project in 20 minutes. My CPU runs at 50%. This is typical for my processor. This has been beaten to death in different threads, but I've not seen a "solution". This is a case where I'm not sure there is an issue to begin with.

[Adam Stanislav]

Originally Posted by Jeff Harper

I've not seen a "solution".

I'm not sure I'd want to do this, but you could always start the task manager (in Vista you press ctl-alt-del and choose Start Task Manager), find Vegas in it, right-click on it and change its priority to Above Normal or even High (but definitely not Real Time, as that may interfere with file writes).

That will force Windows to assign Vegas more processing power than to other tasks currently running on the computer (of which there always are many). It will also slow everything else down, so do not do it if you like doing other things with your computer while waiting for Vegas to render.

It may also help to get rid of unnecessary background processes, which is a bit complicated by certainly worth it (for example, you may take a look at the Disabling Features and Annoyances section of Windows 7 How-To Articles, Tips, and Guides :: How-To Geek).

[Jeff Harper]

Adam, their is no solution because there is no problem.

[Adam Stanislav]

Originally Posted by Jeff Harper

Adam, their is no solution because there is no problem.

I agree. I just offered that if it makes someone feel better. :) I actually tend to do the opposite with programs, like POV-Ray (POV-Ray - The Persistence of Vision Raytracer) that tend to grab too many computer resources, with which I lower their priority to Below Normal, so I can use my computer while they are doing their job.

[Jeff Harper]

I see :)

[Mark MacLean]

Originally Posted by Jeff Harper

Mark, why do you expect your PC to run at 100% for Vegas? Where do you get that expecation? It is not printed or written anywhere. If it did run at 100% it would indicate the processor was being overworked, not that it is running well. 40%-60% is normal. But it varies a lot depending on the processor.

The numbers you should be looking at are how long it takes to render video, which you do not mention. You are leaving out the most important piece of information.

I render a 90 minute project in 20 minutes. My CPU runs at 50%. This is typical for my processor. This has been beaten to death in different threads, but I've not seen a "solution". This is a case where I'm not sure there is an issue to begin with.

I am trying to render some AVDHD video from a Sony camcorder into a simple AVCHD output which is basically just contatenating the files together. Once I get that basic thing working I'll spend time to clean up the footage.

I find that it is taking about 30% CPU and rendering a 10 minute project in about 60 minutes. I was hoping for faster and expected that with 6 cores Vegas would be able to take advantage of them. I have the preferences set for 16 threads, but that does not seem to do the trick to minimize the recode time.

I'm just trying to see if there is something stupid I am doing which is limiting the speed of the render; it looks to me like fileiosurrogate is the bottleneck (taking about 1 core of CPU) but I don't have any idea of why that is the case. I have done some searching and it may be that that is just normal for the kind of video I'm working with.

If it's normal then I guess I just relax and let it run...

-Mark

[Gregory Gatz]

No real help here, but just sharing my experience.

My system is built around an i7 980X, and I have found that processor utilization during rendering varies considerably from codec to codec, while render speed scales closely with processor speed, and is only affected minimally by amount of RAM ( over 6gb ), RAM speed and where and what kind of HDD my files are located.

This Rendertest-2010 –
Sony Creative Software - Forums - Vegas Pro - Rendertes-t2010

....over at The Sony forums, is basically a test of rendering 10 seconds of effects and generated media to a 1080 60i .m2t file.
It uses 100% of 12 HT cores on my system. I found that increasing my video preview from the default 350mb to 1gb decreased render times about 6%, with no effect by increasing it beyond that.

Most of my current source footage is 720 x 480 .avi captured from mini DV from various cameras I have owned over the last few years. I render primarily to DVDA NTSC wide screen with an 8mbs CBR, best quality, and my CPU utilization stays in the 18-24% range .

I have experimented briefly rendering to other codecs, but I don’t recall seeing anything near100% outside of the test mentioned above.

I’m not sure what drives CPU utilization, but based on the test, there is nothing keeping Vegas from using 100% when the job allows it.

It may just be the nature of the rendering process that does not utilize more of CPU resources than it does, while definitely doing it faster on higher clocked CPU’s..

[Jeff Harper]

I just experimented on your behalf, but the thing is we have different processors. I took 10 minutes of AVCHD footage and rendered it to AVCHD and it took 32 minutes. I'm using the old i7 920. Your chip, is of similar speed to my old chip, but your rendering at twice the time. On the other hand I am overclocked, which does make a difference.

If you're not overclocking, consider it.

I don't think you are running too far off from what you should be but you should be discussing this with others that are using the same chip...that is how you find out what is really going on.

1.If your footage is jerky and full of movement, it will slow things down a bit.

2.If your source footage resides on your OS drive, move it off, that is a no-no.

3.You don't have to output to a different drive than the source drive, but it's nice when you can. The main thing is to not have footage on your OS drive.

4.Try overclocking it if you can. I seem to remember when I oveclocked mine it increased the numbers across the board, kind of opening it up. At least that's how I remember it, but it's been a long time ago since I set it up.

[Roger Shealy]

Try CPU Only. It sped my renders up 40% from 7D footage to 60i mp4.

[Jeff Harper]

Gregory, there is never a reason to raise your preview ram above the default, doesn't help anything. It cause problems if it does anything. Edward, correct me if I'm wrong on that.

Raising it to 1GB is completely off the chart...I could be wrong...I don't know. I have ran mine at between zero and the default values for years and it seems fine to me. Mines currently at default value.

Roger, what is CPU only? A program?