Slight improvement-Dualies running V4

LooneyTunez wrote on 7/20/2003, 2:45 AM
For those of you running V4 on dual processor machines, and have experienced the diminished performance (vs. VV3 which is more dual processor friendly), I have a solution that may provide a little relief.

Win2K and WinXP (and NT4 for that matter) have the ability to set "Processor Affinity". In short, that means you can specify which processor (CPU 0, CPU 1, etc) will be used for any running program file/application. On my system V4 runs on CPU 0, but I can set the affinity so that it uses both CPU 0 and CPU 1 by going into the "Windows Task Manager", going to the "Processes" tab, Right clicking on "Vegas40.exe", choosing "Set Affinity", and then putting a tick in "CPU 1".

Doing this doesn't really make V4 a dual processor application, but it seems to give CPU 0 a little relief, and doles out some processing (to an otherwise idle) CPU 1. I have a project that starts to stutter in the middle of the song when only using CPU 0 (which is pegged at 100%). When I set the affinity to use both processors, CPU 0 dropped down about 10-15%, and it looks as though that 10-15% is now going to CPU 1, and it doesn't stutter anymore. While this is not a huge improvement by the numbers, it fixed the issue I was having.

BTW, setting affinity in the "Windows Task Manager" is only temporary, and will default back to using only one processor after you close and reopen the application. In order to set the affinity permanently for a given application, there is a utility that M$ offers that will allow for this. More info can be found here ( http://www.jsiinc.com/SUBH/TIP3500/rh3542.htm)

I don't think there is any risk invovled by doing this, but don't take my word for it, because this may or may not work for you...I just thought I'd pass the info along to you.



Comments

pwppch wrote on 7/20/2003, 3:12 PM
You are imagining things. I can assure you that your affinity setup will do nothing - regardless of what you "believe" or feel you are getting by doing this.

In fact, if you are finding that Vegas is starting on a SMP box with a single CPU affinity, then something is VERY wrong with your system. Vegas will always recogonize mutliple CPUs on a SMP system. Perhaps you are attempting to run Vegas in a compatability mode under XP?

Vegas - and ACID - by design are Multithreaded applications. This is the ONLY requirement to support SMP systems. There are some optimizations that can be done, but in general being multithreaded is all that is required to take advantage of SMP systems.

A note on the changes from 3.0 and 4.0:

The changes between 3.0 and 4.0 in Vegas and ACID was that we added support for ASIO. ASIO is a low sample frame size driver model that prevents anykind of heavy buffering between the rendering engine and hardware i/o. Essentially Vegas 4.0 lowered its thread count in the audio engine thereby loosing some SMP throughput that was available in prior versions. The is a trade off. We needed low latency i/o for ACID's softsynth support and for Vegas' input monitoring. By doing this we traded off SMP performance.

Having said all of this, we are looking for a mechanism to improve our SMP performance in the audio engine for the next releases of Vegas and ACID.

Peter
LooneyTunez wrote on 7/20/2003, 4:46 PM
Peter,

I appreciated your insight on this (as I'm sure you've got more expertise and knowledge than I do), but I can assure you there is a performance increase of V4 on MY system by setting the affinity to both processors. Whether it's technically correct or not, I can't deny the fact that the stuttering of a very processor intensive project stopped when both processors are enabled for vegas40.exe. It's also evident in the "Performance" tab of "Windows Task Manger". I do have quite the imagination, but I'm afraid it's not in this case here. :)

I need some clarification. You said that Vegas should be starting with the affinity set to both processors? That doesn't seem to be the case for me (and there are a few other processes using both), and I can assure you my system is setup correctly and I'm not using any compatibility modes. It doesn't appear that VV3 is starting with the affinity on both processors either.

If you want to take this discussion private, I'll send you my system specifics and some screen shots of processor usage when changing affinities that will demonstrate what I'm talking about.

I'm not trying to be a pain Peter (and I'm sure your theories are correct), I'm just actually getting better performance with V4 set to both processors.

Thanks.
fishtank wrote on 7/20/2003, 9:12 PM
The performance difference from Vegas 2 to Vegas 4 on my SMP system is HUGE. I do not claim to know all that much about multithreading and SMP, but the second processor is almost idle while the other is pegged in V4. This seems to be a poor implementation at best. I'm still fumed about spending all the money on my computer only to loose performance with the Vegas 4 upgrade!

I have noticed that the load alternates between CPU 0 and CPU 1 each time I start playing (Win2K). Not that this makes anything better.
Geoff_Wood wrote on 7/21/2003, 2:56 AM
The difference between V2 and V4 is significant on any system. Version updates are not about improving performance statistics - they are about adding functionality. Some increasing in functionality may reduce 'performance' on a given hardware/software platform.

Presumably you paid the money in order to gain use of the greater functionality rather than just to make the old stuff run faster ? If we now have busses and automation, etc, resources to run those must come from somewhere....

geoff
fishtank wrote on 7/21/2003, 8:59 AM
Bulls#it!

I was seeing substantial gains running a dual processor machine with V2 and lost most if not all of that with V4. SF choose to make tradeoff's\shortcuts and screw the SMP guys using V4. There seems to be very few of us around runinng duallies with Vegas so I guess they decided the loss of performance for us wouldn't matter that much even if we end up switching to a different software platform as there are not many suffering.

The problem is that V4 still does not work that well for me. I love many of the new features but just recently tried to run audio out (1 track) to a high-end analog comp and back with NO success - clicks and glitches galore! I only had about 12 tracks running in the project and a buffer size of 512 samples. Seems if you try to run Waves plugins the ASIO interface struggles (I did try disabling them as well). I am 98% confident my system is *tuned* properly. The fact is that Nuendo performs much better and there are users running systems nearly identical to mine with MUCH better results (WAY more plug-ins and tracks). The initial release of Nuendo 2.0 had issues with CPU usage on Mac's - this was addressed with the 2.01 version about a month later. Don't try to tell me that updates are not meant to fix these issues and that it is *OK* for new versions of software to have worse performance. If a Direct-X plug-in has been improved sonically at the expense of CPU usage that is one thing. When the exact same Direct-X effect runs much worse with a new version of Vegas it is another. I could have tolertated a slight hit mind you, but not 1/3 of my horsepower!

If you are happy with V4 that is great, but please do not try to tell me that I should be happy in my situation. I have always stated that SF has dones some things very well but they have just not kept up with their competetion is some areas. I have been hanging on to Vegas by a thread but have just about come to the point of switching since they obviously can't get V4 completely right and are now talking about V5 having all the *stuff* we have been asking for. How long will it take for the V5 version to work properly? Remember that not all users are having the luck you are with V4 - read the posts!

BTW - to the original post. I checked the Task Manager and my CPU affinity shows both CPU 0 and CPU 1 checked by default for Vegas.exe Sounds like there is something wrong if you have to manually check it.
pwppch wrote on 7/21/2003, 9:41 AM
>>I'm not trying to be a pain Peter (and I'm sure your theories are correct), I'm just actually getting better performance with V4 set to both processors.
<<
I never thought that you were trying to be a pain. I just can't imagine why Vegas would be started with a single CPU affinity under XP. Something is up.

If Vegas is starting up with a single CPU affinitity, then changing the affinity to use all available CPUs would absolutly improve your CPU usage and make Vegas feel/perform better.

I will have to look into why this could happen. We do nothing in Vegas to control the affinity and rely completely on the OS to properely share CPUs across mutltiple threads.

Peter

LooneyTunez wrote on 7/21/2003, 9:55 AM
This is interesting Peter. Fishtank's system is starting with both CPU's, but mine never has (even when running Win2K - I just switched to XP). I'll look into it as well. Let me know if you find anything.

Thanks again! :)
pwppch wrote on 7/21/2003, 12:11 PM
You are running XP pro, correct? Did you check the compatability tab of the properties for the Vegas icon on your desktop?

Peter
LooneyTunez wrote on 7/21/2003, 12:55 PM
Just found something very interesting. I reinstalled my OS again (XP Pro). I have always installed the HAL as "MPS Multiprocessor" in the past (due to reports of ACPI having troubles with audio). This time I re-enabled ACPI in my BIOS and installed the HAL as ACPI. Guess what? I've got affinity on both processors for just about everything now (which wasn't the case before - only a few things would actually be running on both). Not sure if this is a problem with "MPS Multiprocessor" or with my Motherboard/Chipset (Tyan Tiger MPX), but whatever the case, it seems fine now. Hopefully none of the so called (and probably unsubstantiated) "issues" with ACPI will happen.

Peter, thanks for your input...it forced me to check things on my end, and I solved my own problem. :)

Thanks again!
JoeD wrote on 7/21/2003, 2:27 PM
I'm REALLY hoping V4 gets the serious attention to the important details from the dev dept. as it should (loss of power is a NO-NO, any way you slice it).
Then I can dive in and put DVD arch to some good use. Until then it's V3c, Sonar2, Nuendo, Samp.

In the interum, I still have to ask why those of you who do own V4 and it's not useable for you yet, aren't demanding your cash back and just using V3c at this point? You can buy it when it's ready. Those "features" are slim to none on the importance scale over the problems.

Yes, buying new software helps this flagship product and a company in need...but leaving holes in accountability leads NOWHERE even faster.

You've shown you want to buy it, found out some bothersome results, now it's time for accountability on their end. If you show you won't put your money in for sub-par functionality - yet are still showing your intention to buy their product - then it's in both parties best interest to better streamline\fix this flagship product.

It won't happen if you're complacent however. Accounting will just count the $ and the products problems will flow along (joke: it's a "feature" by now).
I know you like SF, I am hoping for a better SF...but nothing is going to be done if you don't LET MONEY TALK. It's not a personal thing...it's just plain 'ol business.

Pull your purchase and use V3c, they'll get the msg loud and clear.

JoeD
Geoff_Wood wrote on 7/21/2003, 3:47 PM
fishtank : "Bulls#it! I was seeing substantial gains running a dual processor machine with V2 and lost most if not all of that with V4. SF choose to make tradeoff's\shortcuts and screw the SMP guys using V4. ......Remember that not all users are having the luck you are with V4 - read the posts!"

Yep, I've read the posts. Looks to me as is some users have messed up systems, and others haven't. Glad the area of screwedness is closer to being identified so those with a problem can fix it

geoff
LooneyTunez wrote on 7/21/2003, 4:07 PM
After more experimentation, I have found that "MPS Multiprocessor" vs "ACPI" is not the issue at all!! I use a third party software for my Nomad Jukebox 3, which integrates itself into "Explorer", and that program does not support SMP. Once this program is activated it kills "CPU 1" on any newly launched applications. As long as I don't use this third party software, the affinity of Vegas and all other apps work with both processors. I'm in the process of writing an email to the software designer to see if this can be addressed. Sorry for the confusion!! :(
LooneyTunez wrote on 7/23/2003, 11:09 AM
Just discovered something even more interesting, and I'll ask you guys with dualies to try an experiment (to see if you get the same results).

Open "Task Manager" go to the "Processes" tab, and check the affinity of "explorer.exe". It should be set to "CPU 0" and "CPU 1". This is how it should be, and when you launch Vegas or any other multithreaded program, you will have affinity on both processors for that program.

Now, this is the weird part. Open "My Computer" or "Windows Explorer", and find a DLL file. Right click it, and choose "Properties" (maybe even move through the different tabs) . Now, go back into "Task Manager" and check the affinity of "explorer.exe" again. On my system, "explorer.exe" is now only on "CPU 0", and any subsequent programs that I launch (Vegas, Sound Forge, Notepad, etc) will now only have their affinity set to "CPU 0". I have found this happens when checking the "properties" of many different file types (but not all of them - .wav, .mp3, .doc are fine). It makes me wonder what other normal functions of "Windows" may cause "explorer.exe" to change it's affinty.

BTW, a reboot puts everything back to normal (for a while anyway).

Have I found a possible bug in "Windows", or am I just on crack?!

See what results you get guys...

Thanks.