Low CPU usage on rendering

a1base wrote on 12/10/2020, 9:48 AM

I'm running Vegas Pro 17.0 (build 452) on a Ryzen 3700x system, and rendering 1080p videos at 60fps. Until recently the software performs as expected, loading all 16 threads to 100% and chewing through the rendering process.

Recently however, The CPU usage tops out at 50%, and it's not even loading all the cores evenly. The last 4 cores are maxed out in usage, while the first 4 are less than 10%. The others vary incrementally.

I'm using saved project template and am rendering to the MAGIX AAC mp4 format using the internet 1080p 59.94 fps template, so I'm not sure how anything could have changed.

I'd really appreciate any ideas of what might be going on? Obviously my rending times have doubled which is a bit of an issue for production. The system is performing no other tasks at the time of rendering that would be utilizing the CPU.

Thanks

Will

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Comments

RogerS wrote on 12/13/2020, 11:37 PM

@lenard I totally agree a single number for GPU use doesn't tell you much, and included other graphs above for that reason.
Is what you are saying though that you would get better CPU performance with the same type of transcode test if you unchecked GPU preview acceleration, but still left decode or encode on? (assuming there weren't stability issues)

RogerS wrote on 12/14/2020, 12:19 AM

FWIW, in my case (i7700HQ; GTX 1050) disabling preview acceleration only slightly slowed things down (~20 sec.) compared with my previous test. New #s are 9:30 and 1:30 for 4K to 4K, CPU and GPU with respective MagixAVC render templates. I'm curious to see how a beefier CPU compares.

walter-i. wrote on 12/14/2020, 1:58 AM

Ram isn't the same as dynamic ram preview.

@RogerS
I edited and clarified that in my previous post.
I meant - of course - dynamic RAM preview.