Actually, very short projects (the total length of the project in the PPBM5 benchmark is less than one minute long) will not show much if any performance advantage of direct export over queued. Longer projects are required to see much if any difference between the two (and this difference does not show accurately or consistently in benchmarks).

One hour AVI, 3 minutes MPEG and 1 minute H.264 are all much better than 15 seconds that Tom is talking about.

You might want to read this:
Adobe Forums: Mercury, CUDA, and what it all means

I must admit I must have been wrong about terminoloy given that Adobe employee said the following "It's worth mentioning one set of things that Premiere Pro CS5 doesn't process using CUDA: encoding and decoding." This means I was wrong when I said "Premiere's encoding process DOES use CUDA MPE." However, this doesn't not mean I was wrong when I said using export is faster than using queue.
Having said that, let's go back to the root of this confusion.


By Luis de la Cerda

"Eric, for GPU assisted rendering try file->export from the premiere timeline and instead of clicking on "queue" after choosing your export settings, select "export". In my experience this results in 2-5x faster rendering."

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By Harm Millaard

"Luis, Rendering has nothing to do with exporting. Rendering is only for previewing the time line.
Exporting and thus encoding is a completely different and unrelated thing, just as washing your car and driving it are unrelated and completely different.
Exporting directly or via the queue can result in slight performance differences, but nowhere near 2 - 5 times. Sometimes it is faster, sometimes it is slower, but generally they are about the same, at least that is what Adobe wants it to be. Depending on the export format used you may get slightly better results with one approach, with other export settings it may be the other way around."

Randall Leong
"That does not happen in my system. In fact, in my system exporting via the queue took six times longer than exporting directly, when it comes to HD-to-SD encodes from HD AVIs. It could be something wrong with some part of my system."
-----------------------

What I argue is that Luis de la Cerda and Randall Leong is right on this case. As illustrated in my test along with others, using 'export' can be a lot faster than using "queue." (After all, this is what people have been saying all around forums since CS5 came along.)

They're only about the same if you're just doing full size to full size transcoding without applying any CUDA accelerated effects. I'm not sure what this process should be called now as using the term 'encoding' doesn't seem to fit in here if we want to be technically accurate.

Now, I learned that CUDA MPE doesn't play a part in the actual encoding process but it handles other processes(resizing, effects...etc.) freeing the CPU so that it(CPU) can work on actual encoding process.
So, while you're right that CUDA MPE doesn't do encoding, you're wrong when you said using 'export' and 'queue' is about the same in terms of encoding speed. And, it's not something I need to prove again. Look around forums and listen to what people have been saying all along. Using CUDA MPE does speed up the encoding process and you know it.

Actually, I agree with Harm because I only used AVIs when I tested the export versus queuing. If the source files brought into Premiere had been already lossy-compressed H.264 files, and especially MPEG-2 files, my results may very well be different.

And yes, exporting to AVI will always be faster than exporting to H.264 or MPEG-2.

The PPBM5 benchmark tests, for what they're worth, actually use already lossy compressed source videos, which are by their very nature more difficult to edit than AVI files. Thus, the longer times for encoding from such sources are due partially to the fact that CS5, like most other "prosumer" NLEs, actually "convert" to uncompressed RGB within the NLE itself - and this eats up some of the CPU's power.

UPDATE: I managed to run the MPEG-2 DVD portion of the PPBM5 benchmark both direct export and queued. I did pretty much confirm Harm's results there - only in my case, it took nearly double the time direct as it did queued. Only part of the reason for the (relatively) worse direct-export result is the lack of a hardware RAID controller (and thus, I'm currently limited to a KISS setup rather than a LOVE setup).

"Actually, I agree with Harm because I only used AVIs when I tested the export versus queuing. If the source files brought into Premiere had been already lossy-compressed H.264 files, and especially MPEG-2 files, my results may very well be different."

By that, are you saying you agree with Harm saying "Exporting directly or via the queue can result in slight performance differences, but nowhere near 2 - 5 times. Sometimes it is faster, sometimes it is slower, but generally they are about the same, at least that is what Adobe wants it to be. Depending on the export format used you may get slightly better results with one approach, with other export settings it may be the other way around."?

If so, why am I and others getting more than 5x times of speed increase when using export function compared to using queue? Why does GPU load stay in 80-90% when using export? And I'm not talking about AVIs here but h.264 files as OP mentioned.

Alright Harm, now I see why you don't see what I see.

The difference is caused by this setting: "use maximum render quality."
With that off, there's no major difference between export and queue. With that on, the difference in speed is as great as 5x and I suspect others' with a faster GPU than mine (I use DDR3 version of GT 240 so it's around 50% slower than DDR5 one) may see around 10x of difference.

So you were wrong when you said "Exporting directly or via the queue can result in slight performance differences, but nowhere near 2 - 5 times. Sometimes it is faster, sometimes it is slower, but generally they are about the same, at least that is what Adobe wants it to be." Just like how I was wrong when I thought CUDA MPE does encoding. It 'helps' encoding but it 'does not do' encoding.

While we were both wrong on certain matters, there's something else that differentiate us: you were being ignorant. Your saying "Run the PPBM5 Benchmark and you will know. Your claim is utterly untrue, unbelievable, unsubstantiated and lacks all kinds of proof, for others to test." proves it.

You knew there're people who witness this type of difference in speed (http://forums.adobe.com/message/2839569#2839569 http://forums.adobe.com/message/2805313#2805313) yet you didn't bother to furture investigate the issue and cause of it. You gave it a try but when you couldn't find an answer, your ignorance took over your intelligence.
When others and I peronally presented findings, you failed to take it into your consideration. Instead, you made nothing but a rant based on your ignorance. Your narrow mind couldn't digest the fact that there're things you still don't understand.
What's somewhat funny is when you said ""I've gotta see it before I believe it, said the blind man."in above mentioned link. Yes, you were being a blind man and because you were blind, you couldn't even see others and my findings. You couldn't even see yourself.

"The difference is caused by this setting: "use maximum render quality."
With that off, there's no major difference between export and queue. With that on, the difference in speed is as great as 5x and I suspect others' with a faster GPU than mine (I use DDR3 version of GT 240 so it's around 50% slower than DDR5 one) may see around 10x of difference."

You are correct. With MRQ on, the export is even slower than the queue. No difference with H.264, but MPEG2-DVD is around 30 seconds slower than without MRQ and nearly twice as slow as the Queue.

The only difference between your opinion and mine is that export is always equal or slower than the queue and you persist in claiming 2 - 5 times faster performance without giving proof.

Example with MRQ on, MPEG2-DVD export is 147 s, queue is 80 s.

I found that when exporting a SD mpeg2 from 1080p xdcam with max quality, doing it directly from premiere is way faster than using media encoder, which is in line with Tom's experience. I see a high GPU utilization vs. very marginal one when encoding in AME.

Just recently I was exporting a multicam edit and did a test render.

57 mins long xdcam 1080p sequence was encoded to mpeg2 SD in around 15 minutes (very high gpu util.)

No color correction, no effects, max qual. render checked.

After that I set the dvd chapters and the sequence went to encore via dynamic link and it was encoded there with AME with exactly the same settigs as the test render. It took around one and a half hour (low gpu util) to finish.

i7 950 @ 4ghz, 24gb, gts450

Actually, there is a possibility that performance in queued mode might be embarrassingly slow compared to the export mode if the CPU is running overly hot during queuing (this can occur with a heavily overclocked CPU). I will try another clip - this time, an already-compressed AVCHD camcorder clip - for this possibility.

Do you realize that XDCAM is not AVC - but MPEG-2? MPEG-2 HD decoders are relatively mature compared to AVC(HD) decoders. Harm's testing (as bourne out both in the PPBM5 benchmark and of his own new tests) involves just one type of HD source - AVC(HD).

I don't think that's the case here. My cpu is watercooled and after few hours of number crunching at it's max the temperatures are lower than with stock cooler at stock frequency.

Moreover, it has nothing to do with different gpu utilization

In your case, it has something to do with your source video. As I stated in my previous post, XDCAM (as used by your particular camcorder) is not AVC(HD) - but a variant of MPEG-2 instead.

nevertheless, how would you explain the noticable difference in export times and gpu utilization between premiere and ame with exactly the same settings?

Actually, it comprises DV, HDV, XDCAM and AVCHD, both progressive and interlaced, and at 24, 25 and 29.97 fps, plus some synthetic clips. Both in the PPBM5 test and in the new test.

From the background page on the PPBM site:

The source material is heavily mixed, it comprises DV AVI in PAL, HDV 1080i PAL, XDCAM-EX HQ PAL and AVCHD 1080 NTSC.

Thanks for the clarification. It still does not explain why my previous HD-to-SD encodes in queued mode are many times slower than in export mode. This is why I will be using a different type of HD video source format to check it out. Maybe it is my "source" files (Cineform and uncompressed AVIs) to begin with?

And yes, I agree that mixed source files tax the system even more than single-format sources.

UPDATE: I retested my system with a 6-plus-minute AVCHD clip, and my results are pretty much the same as with the AVI: The export speed to MPEG-2 DVD is faster on single layers than queuing. But the, I experimented further with more layers, and the speed advantage of exporting directly diminishes greatly - and often more than completely disappears.

In other words, those that gotten faster results with exporting over queuing obviously is performing simple, single-layer projects -- something that a much cheaper, consumer editing program can easily perform. In this "simple" task, queuing places a much greater load on the CPU than direct exporting does.

On the other hand, if one is getting unbearably slow performance with even simple video transcoding/resizing tasks in queued mode, the system is just too freaking slow overall.