Rendering a project that contains nested projects is slower than rendering a project without nested projects. In my experience, by a factor of 4.

The template you are using makes a huge difference. The speed of your disks, and the number of disks, memory speed and timings, they all enter into the mix.

So, you are basically saying, drop the nested project stuff, render to some more or less lossless format and do the final render with the intermediate renders.

If the CPU isn't working hard something else is the bottleneck.
First thing I'd consider is the disk system thoughput especially when lots of media from different source files is involved.

Bob.

i somehow never thought of vegas pro as 'four cylinder', maybe movie studio...

i'd think vegas was more a refined six cylinder, and something along the lines of fire / flame / smoke 12.

that said, 11 ran like an east german 3 cylinder and 12 is more a sort of wankel, great on paper but not quite the same in real life....

ah, render due to finish....

"Rendering a project that contains nested projects is slower than rendering a project without nested projects. In my experience, by a factor of 4."

I've had the same experience with nested projects so I don't use them. My solution has been to do a final render for each of the "nested" projects and then combine these using third party software that will smart-render the files together. I use TMPGEnc's MPEG Editor. Similar software is available if your final render format is AVC.

Another way is to use the the stitch option in the Transcoder if you have Vegasaur.

wwaag

There was a thread about four years ago that discussed why all the cores of a CPU were not running at 100% during a render. JohnnyRoy posted the following which is as good an explanation of what's happening as I have heard:

What people who don't understand how computers do multi-tasking don't realize is that multiple cores can only be utilized when the task has steps that can be done in parallel. Work doesn't magically use all of the cores at 100%.

You can read the entire thread here:

www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=586955

FWIW. For grins, I just rendered two nested projects in V12. Total duration was 9:51. Clips were mostly AVCHD (1080 60P), with some MPEG from Proshow Producer and Cineform AVI,s--all were 1080 60P.

First render--internal mainconcept-HDV (1440x1080, 60i). Render time: 16:28. Using task manager--my guess is that average CPU usage was around 80%.

Second render--Debugmode Frameserver to Grass Valley Procoder (IMHO a lot better than MC)-HDV (1440x1080, 60i). Render time: 10:29. Here's what's interesting--my guess is that average CPU usage was around 40%.

Bottom line: Procoder was a lot faster, although CPU usage was dramatically lower--reinforcing John Cline's previous post. Procoder does a lot better at distributed processing.

wwaag

@Terje:

Nesting is a great tool for editing, but remember that at render time, all the rendering work still has to be done on the nested projects as well as the top level project. So rendering the nested projects out to a good intermediate really does not cost you time.

As an experiment, I tried running the New Rendertest both nested and not, with and without GPU on my 3770k with GTX 660ti:

1. Rendertest from internal SATA to USB3 no GPU:

Elapsed time 3:23, averaging 0% gpu, 65% cpu     NOT NESTED

Elapsed time 4:31, averaging 0% gpu, 16% cpu     NESTED



2. Rendertest from internal SATA to USB3 Rendertest.veg with GPU

Elapsed time 0:36, averaging 70% gpu, 50% cpu   NOT NESTED

Elapsed time 0:55, averaging 50% gpu, 16% cpu   NESTED

There is a measurable difference on this machine in elapsed time, although nowhere near the 400% I have seen on less powerful machines in the past. Very interesting that GPU made a huge difference.

Edit to fix a header

I avoid nesting at all costs. You can render to an uncompressed file far quicker than any compressed file. If disk space is a concern, you can always delete the uncompressed when you are done, plus in video, if disk space is a problem, then the computer needs to be upgraded. You just have to have a lot of disk space in this field.

I use uncompressed for all intermediate files.

Dave T2

<<So, you are basically saying, drop the nested project stuff, render to some more or less lossless format and do the final render with the intermediate renders.>>

YES!

I render to the .mxf format - the quality is excellent and Vegas handles this format really well. I use the HDCAM EX preset but others might work just as well for you.

If you get a video card to help accelerate timeline playback and rendering performance you may want to try V12's MP4 rendering format. The quality is good and it renders quickly.

farss >> If the CPU isn't working hard something else is the bottleneck

Doesn't seem like it. Seems like it is poor execution of rendering nested projects within Vegas. Proof? I think so. I fire up five instances of Vegas, one for each of the nested projects. I kick of rendering for all of them, and voila, 100% of CPU used, and the render of the combined projects is significantly faster than rendering it from the "mother" project.

Given the fact that the easiest way to split the render into multiple threads would have been for Vegas to essentially do what I do, render each project in a different thread and stitch at the end of the last render.

For nested projects at least, it seems SCS has a potential of about a 200% speed increase by just fixing the threading issues Vegas apparently has for nested projects. Considering that this is a significantly safer route to go than adding GPU rendering into the mix (obviously, see the complaints department) it would probably behoove SCS to look into this.

Think about the messages you are reading in this thread alone "never do nested projects", "nested projects don't work", "nested projects a nightmare to render".

I love Vegas, and I since 12 I am back to using it as my main video editor, but if it can't handle nested projects properly, that might change. SCS needs to focus on where they lag the competition and where they are strong. Premiere has "nested projects" and the execution is (comparatively) flawless (not in an absolute sense, I know) and other neat things. Does Vegas do render queues? It's a good idea. Instead of having to fire up four instances of Vegas and render in parallel I could have added them to a render queue, and had the master project render from the pre-rendered (MXF for example) video files. That would have been nice.

So, here is what I put on the top of my wish list for Vegas 13:
1/ Fix nested projects, if your users say "never use nested projects", you have failed badly. Nested projects is a very, very good way to work. In fact, look at Premiere. Adobe does this the right way, SCS not so much.
2/ Check out the threading stuff, seems like there is some enhancements needed
3/ Fix the apparent (but not seen by me) problems with GPU rendering
4/ Stop making me have to agree to the license terms each and every time I run Vegas. I know, I am on Windows 8, but I agree, I promise. Once is enough.

I'd pay for an upgrade if only 1 was fixed.

I would not pretend for a moment to know threads, cores, and CPu cycling...but, there could be a point here, IF I know the real score on programming this kind of feature. That is a lot of underthe hood examination. WOULD assigning a thread per nested project be possible? ON all makes of CPU's with multiple cores? Can it be that simple?

Ok, if it is, then go for it and goodness gracious, lets get rid of this GPU bamboozlement!