Vegas rendering - Low cpu usage on 8-core

[lapoune]

Specs:

cpu: 2x QX9775 (8 cores)
HDD: Spinpoint F1 raid 0 (2 drives)
ram:8gb 800mhz

Hi,

I built a computer in hopes of reducing our renderings times. Problem is, anything greater than 2 cores show very little gains. Going from 1 core to two cut the time by more than half. If I add any more cores the gains diminish a lot and cpu usage when using all of the cores is less than 50% on each. I'm starting to think the hard-drives might be the bottleneck but I was hoping some of you might have an idea or faced a similar problem.

I will try running multiple instances and overclocking the processors to see if it has any effect on the times. Sorry for my butchered english it is not my first language.

Thank you

[aedipuss]

you might get better results with 2 separate drives, a source and a destination. but having said it, here on my system even with 4 separate drives, vegas doesn't max out my q6600 quad core. i haven't done the math but current drive i/o throughput is about 66MBs, so the bottleneck might be there.

[SCDVD]

The article in this link indicates that Vegas and other editors don't appear to use more that 4 cores. I guess we will have to see in a year or so what Vegas Pro 9 looks like.

http://www.eventdv.net/Articles/ReadArticle.aspx?CategoryID=229&ArticleID=40442

[lapoune]

well here's an update...

I am now 99% sure the bottleneck were the hard-drives. After some testing, rendering finishes about 20% faster by adding a second drive and cpu usage climbed into the 50s (from about 45%).

I ordered 6 Samsung F1 320gb. They use the same platter as the TB (so same performance, without the wasted space, at 65$ each). I curious to see how much I can get out the the onboard raid controller.

And BTW all 8 cores are used, though it is as fast if I use only 4 cores (about 80% usage). The remaining cores will probably come into play once the hard-drives can catch up.

[ronnylov]

Before buying all these hard drives maybe you can create a RAM-disk and try files directly in RAM-memory to see if it really helps.

There is a free ramdisk called gavotte ramdisk that should work on vista x64 but I have trouble finding any good link to this driver...

[JohnnyMalaria]

An easy way to get an idea if the hard drives are the bottleneck:

Use Windows to copy your source video file to your destination. This will tell you the absolute minimum time it will take to do whatever you are going to do. Then just compare it with the actual time - odds are it will be a significant chunk when crunching on a quad or oct core system.