Make QT export faster? Not using resources.

Question

I am exporting some quicktime movies to DV clips. These clips are 640x480 and anwywhere from 15 to 45 minutes long (however, the following problem happens on QT clips of all resolutions and lengths).
The problem is that the process is very slow, and QT Pro doesn't seem to be using my system's resources very much. I have a brand new Mac Pro (3ghz quad core) with 5 GB of RAM – so obviously I was hoping the new system would speed up this process. But it is not noticeably faster than my old iMac G5.
The "problem" is that I don't think QT is properly using the "horsepower" of this system. The CPU usage meters show all 4 cores being used at only about 25%-30%. However, Activity Monitor shows a process called QTPlayerHelper running at about 125% CPU! (which doesn't seem possible).
As for RAM, Activity Monitor shows all 4.95 of 5GB "used," but Quicktime is only using 100 MB and QTPlayerHelper is only showing 40MB use. But, in another apparent contradiction, it says VM size is over 19GB... if QT, which is the only thing I am doing now, is only using 150 MB of memory, why is VM usage so high?
Other than just some general insight into what is going on here, my real question is: "Is there any way to make QT use all system resources to speed up these exports (so my 4 cores of Xeon goodness would be used to their fullest potential)?"

Answer 1

In Activity Monitor, under the System Memory tab, you will see that RAM usage is broken down into four categories; Wired, Active, Inactive, and Free (shown visually on the pie chart).
Wired: Memory used to run the system (kernal). You can't free up Wired memory since you can't quit the system. Sometimes, a restart will free up some resources here but as you use more of the system, it will claim more memory.
Active: Launching applications causes them to claim various amounts of memory to run. Quiting applications will free up some of the Active memory.
Inactive: Applications may reserve additional amounts of memory that it uses to load a document or cache into so it runs faster that going to the disk each time. Inactive memory is variable, other applications that want to use it can grab it at will. It's basicly like holding a seat in the theatre for a friend, if all the other seats are taken and your friend hasn't shown, you have to give up the seat to anyone that wants it.
Free: Memory that hasn't been claimed or reserved.
The "Used" total includes Inactive memory, but the number in the Real Memory column for each item does not, only Wired and Active.
You may also notice this scenario one day:
10% Wired
40% Active (let's say two applications are open)
40% Inactive
10% Free
---Then you quit one of the applications and see:
10% Wired
20% Active
60% Inactive
10% Free
You didn't gain any Free memory, but that's because as soon as it was available the remaining application reserved it. If the system needs it or you open a new app, it will give it up to it. It's best to think of Inactive memory as Free for your purposes.
As for the QuickTime export...
At some point, there is a limit to how fast something can be done. I'm sure you know that 20%(x4) on a Xeon is at least >= 100% on a G5. Only applications specificaly optimized for quad-core processors can make full use of all it's power. Unfortuanatly, not every program toady has been (or needs to be), which was true when dual-core computers first came out. In this case, the power of your machine lies it the fact that you can be doing lots of other things at the same time as the QuickTime export without it slowing down. Can't do that on the G5. Right now, the biggest benefit goes to pro video editing and effects applications and specialized math and scientific programs. For the time being, know that nothing can do it faster than you can and you don't have to take lunch while it exports, you can keep working. 10 years ago, if I wanted to export a 30 minute video I edited in Adobe Premiere, I had to leave it over night, and it wasn't even DV quality or have today's fancy effects. Those were the days...