Blackmagic Forum

I get very choppy/laggy playback & slow rendering while editing. My GPU utilization doesn't go above 12% while rendering or playback. Video files are mp4 (h265/h264). Video clips are 24fps, 60fps, 120fps. Cameras used: Canon C70 / Canon R5. CPU gets maxed out at 100%. Ram hovers between 20gb-25gb usage (system uses 19gb/15% when no applications are running, just idling). This choppy playback occurs whether my timeline resolution and playback are in full-resolution (4k DCI) or in 1080p/720p and one-quarter resolution playback. Rendering has been set to mov, mp4, h264, h265, 4k, 1080p. Utilization is always the same. NVIDIA control panel is all set for performance. 3D settings is set for video-editing as well as the "enable video editing mode" option. And yes, i've tried changing all the options, setting to defaults, messing with everything. No change in performance or utilization. In davinci, my memory limit is maxed to 75% usage (95gb). Playback and rendering seems to only be using my CPU and even with that, it should playback smoothly. I've installed every new driver I could, updated windows 10, reinstalled davinci, etc. It's almost like something is throttling my speeds, yet when I ran a benchmark, my score was so high. I've spoken with Davinci tech support and double checked all of my settings in resolve. GPU is set to CUDA, and my gpu is selected. GPU is in 16x PCI-E slot. No other PCI-E slot is being used. Videos and Davinci are both installed/stored on NVME SSDs.

Temps:
GPU: Idle: 42c / Running resolve: 85c
CPU: Idle: 50c / Running resolve: 66c

*Nothing is overclocked

SPECS:

CPU: AMD Ryzen 9 5950X 16-CORE
GPU: Nvidia RTX A6000 (48GB VRAM)
RAM: G.SKILL F4-3600C18-32GTZN 4x31.8GB (128GB)
MBD: Gigabyte X570 AORUS PRO WIFI
NVME SSD: WDS200T1X0E-00AFY0 2TB - 7000mb/s Read / 5300mb/s Write
NVME SSD: WDS200T1X0E-00AFY0 2TB - 7000mb/s Read / 5300mb/s Write
SSD: Samsung 870 QVO 1TB
HDD: Hitachi HDS722020ALA330 2TB - backup hdd
HDD: Seagate Barracuda 7200.14 2TB - backup hdd
Thermaltake Toughpower Grand RGB 850w
(4) Noctua 140mm fans
(3) 120mm Front Fans

if you set the timeline frame rate to 24fps, and play a 1 min DPX file, at UHD res, what is the color page fps?

Assuming this is all 10 bit 4.2.2 nothing in your system can hardware decode it and you're forced to rely on the CPU.

Basing on my own experience: I have 3x 1TB NVMe in RAID0 (huge throughput) - but I didn't waste it for storing applications or media: it's all dedicated to the cache clip. The OS (Windows) and apps are all on a separate, single SSD drive, and the edited source material - on another RAID 0, but one using 4x (rather fast), but traditional and so cheap HDDs....

This way - my 2 GPUs never have to wait for writing my cache files, as even uncompressed ones are written so fast (also when playing the project back, I'm getting full 50 fps for my 4K/UHD 10bit 4:2:2 media/timeline/project settings). While the GPUs are almost 100% loaded at CC cache rendering, at playback time it's my 32-core CPU which get's up to 95% if some serious FXes are used (sometimes considerably less, but - I believe - only due to the suboptimal architecture of this early beast from AMD). Again: no dropped frames!

Piotr

PS. Of course, I rarely use uncompressed scratch files in my caching - but since I edit a HDR timeline, the DNxHR 444 (HDR) format is a minimum for them.

Hey

Without hardware codec support you can forget playing back h265 4k files at more than 50 fps.
( your CPU hasn't any)

However switching to high_performance_mode (windows=> control panels => power options) might help

And things get a little better after enabling largesystemcache, better means workable but not yet perfect.
(with HDD drives anyway)

The follow link explains how to enable this cache

https://ccm.net/faq/7106-windows-7-incr ... disk-cache.


So best to work with proxies, it works faster (and there is no shame in that)

hope it helps

Does the A6000 actually include NVDEC?

AFAIK, that enormous GPU does support hardware decoding, but would that include 10 bit 264/5, which you'd be getting from the C70 and R5?

24p 4k footage from the C70 was unusually demanding of my much older and lesser-powered system, but as an indicator, that footage is particularly challenging. The fact that 1080p timelines with proxy playback isn't working well either could indicate a particular issue Resolve has with the footage. If you upload some samples, others here can report back, even if no one else here has that monster GPU.

John Paines wrote:AFAIK, that enormous GPU does support hardware decoding, but would that include 10 bit 264/5, which you'd be getting from the C70 and R5?
.

Correct, but black Magic has not enabled it for a bunch of codecs even though Nvidia supports it

https://www.pugetsystems.com/labs/artic ... udio-2122/

The problem isn't 10bit it's 4.2.2.

https://developer.nvidia.com/video-enco ... matrix-new

Only 4.2.0 or 4.4.4