My computer is running with intels QX6700 Core2Extreme, and I use it specifically for 3-D and photographic designs. (OS: XP64)

however, when I start one rendering task, only one core gets the job (25% CPU usage).
I can easily start 3 programs like Autodesk 3DSmax and Photoshop CS2, and let every single program render a scene, and then the CPU usage reaches 75% and windows still runs well...

could i get 75% CPU usage with one single rendering task?
every rendering process COULD be 3 times faster done...
maybe theres some software to control this??

please help me out!!
thnxx!!
madmike..

You have discovered the crux of multiprocessor computing...

If you have one process that generates one thread, then it will tax only one processor with that one thread to finish that one process.

You have to have applications that are capable of multithreading in order to tax all the processors, or be able to run multiple threads at the same time and assign the tasks to any of the available idle processors.

As we see newer operating systems and applications take better advantage of the hardware available, you will see less idle processor time and better performance throughput from multiprocessor machines (and I'm not just talking about being able to write an email while burning a DVD and rendering a Flash movie in the background). For instance, if you are talking about a 3D rendering program, being able to render several frames in parallel as opposed to rendering each frame in serial would speed up performance since each frame would be treated as a single thread that could be assigned to any processor which is idle.

It will take a shift in programming before we all feel the advantage of multiprocessor machines, but once this starts to happen, there will be a palpable difference in performance, rather than the lackluster 25% utilization you are seeing now on a quadcore system.

I think that CS3 is supposed to multi-thread better. I don't really know anything about 3D rendering though.

-mcg

MadMike,

First, your nick brings screams to folks around here so please do not be alarmed if you hear some folks giving you some #$%^ about it. It is not you but a former member that had some issues with a very similar nick.

Second, the problem you are running into is called OS priority scheme. In essence the OS assigns a priority to each process and the OS level processes receive the highest of those priorities.

You may hear of this as "Nice or Nicing" a process. Upgrading the priority of a process.

Try reading/doing the info here:

MS_INFO_FOR_PROCESS_PRIORITY

Give that a try and let me know how it looks after that.

Be advised that you can set priority "too high" and cause other things to "wait".

Hope this helps!!

strange I thought that Photoshop was able to take advantage of multiple threads for a while now.

AFAIK most higher end 3D apps are optimised to support multi-core out of the box, 3Dsmax certainly should be among them.

What about that boot ini "set uptimer" thingy that I've seen mentioned elsewhere that can help an XP box make better use of multi core cpu's?

hmmm. AFAIK These programs are meant to be multithreaded. I can't really help you since i'm not a graphics design kinda guy, but i'm sure someone around here can help you.

edit: Woops, must have hit the reply button about 10 minutes ago

You also should look at the programs you're using. I'm not too familiar with 3d rendering either, but it is highly math intensive.. I'd be surprised if any "professional" packages don't use multiprocessing, since unlike many other applications, you -would- get a huge benefit from multiple cores. There may be a setting to enable it, or another rendering program might work better.

I ran across a blog post from one of the Photoshop devs. He claims photoshop does use multiple processors, but that their problem is memory bandwidth - the images are so big that there simply isn't enough memory bandwidth available to feed both cores (a single image file can be 2 gig, which is the max a 32-bit application has access to! No room left for working space)

If just depends how well the application is multi-threaded.

The app may be able to run different tasks each on a seperate thread and hence make use of the multiple processors but a given task may not be multi-threaded. As a result if a single task is doing some serious computing you would still see what you see.

There really is nothing you can do to improve performance from a Windows standpoint.

A software update may help, but I would ask in the vendor's forums.

There are various programs on the Internet that set affinity automatically for you. More for dual core than quad core.

But affinity will not help his situation.

The application is already doing this since when he runs multiple instances of rendering, they load does get put on different CPUs.

That would really only help if everything kept getting stuck on CPU0 and nothing ever cascased to CPUs 1-3.

Zen,

Please look at my post.

He can improve by giving more time to the process via Priority settings.

Me too. I have an old copy of Photoshop 7 and Premiere 6.5 that I haven't installed yet on my new build (QX6700 with 4 gigs memory). But I have installed Photoshop Elements 3 and will check it tonight to see how it multithreads.

One of the first things I did after installing XP MCE and Vista 64 in a dual-boot setup on the new rig, was to look at DVDShrink's multitasking. I ran 2 instances of it - two DVD burners - and looked at what Task Manager reported for # threads and core loading. I'll try to hunt up the screen shots if anybody is interested, but what I recall is that in XP, Shrink loaded 3 cores pretty evenly with the 4th core loaded much less. In Vista 64, all 4 cores were loaded equally and the total time for analyzing and recoding to 60% original size was reduced noticeably too.

So if DVDShrink, which hasn't been updated in what - 2 years now? - multitasks well, I'm surprised Adobe can't make Photoshop or Premiere perform well too.

Scheduling only really comes into effect when the cpu is at its max. If its idle then the application is getting all the cpu it needs. If a lot of cpu is in use the prorities will weight towards what application gets a time slice.

Yes, increasing priority is likely to have very minimal effect.

This would really only do something is there were other major threads stealing significant time. If that was the case, he could then use affinity to keep Process A and Process B on different CPUs. This would likely be more effective than setting a very high priority on the task.

Example - If he said that everytime his AV Updated kicked in, his CS2 slowed to a crawl, he could set CS2 and the AV Updater to use different CPUs. This would work because CS2 basically sticks to one CPU and he would then be able to keep other high utilitzation tasks off that CPU.