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Jerky playback in Studio when all was ok in Free

PostPosted: Tue Mar 02, 2021 2:56 pm
by Daniel Portillo
Until today I'd been using the free version of Resolve (17 b7) but today I finally upgraded to Studio. I backed up the database and the projects, uninstalled free and installed Studio. The two projects I'd been working on were already there (presumably the uninstall hadn't deleted them) and I was able to open them, with everything there as it was before.

However when I played the sequence it played back with judder and a number of 'freezes' between cuts. The timeline (and material contained within) is 1080p 23.976fps, h264. I checked that the settings hadn't changed to output a different frame rate (they hadn't) and have since been through all the settings, making sure it is using my 1080Ti GPU, I've deleted the old caches etc but all to no avail.

I went into the media page just to play the source clips and they also play back jerkily. I didn't have these problems when I was using the free version so does anyone have any ideas as to why I'm getting them now in Studio? If anything I thought performance would be better given Studio utilizes the GPU more?

I'm puzzled....

Re: Jerky playback in Studio when all was ok in Free

PostPosted: Tue Mar 02, 2021 3:21 pm
by Shrinivas Ramani
To check a few obvious culprits...
What is your Nvidia driver version?
And if in the Studio version you uncheck "Use GPU acceleration for decoding H.264" (or similarly worded, under Preferences > system) do you see the performance differ?

Re: Jerky playback in Studio when all was ok in Free

PostPosted: Tue Mar 02, 2021 3:44 pm
by Daniel Portillo
Shrinivas Ramani wrote:To check a few obvious culprits...
What is your Nvidia driver version?
And if in the Studio version you uncheck "Use GPU acceleration for decoding H.264" (or similarly worded, under Preferences > system) do you see the performance differ?


Thanks for getting back to me so quickly. The Nvidia driver version is the latest studio driver 461.72. I just unticked the option "Decode H.264/H.265 using hardware acceleration" and the source clips/ timeline do play back far more smoothly.

That seems counter-intuitive to me. Is this a driver thing?

Re: Jerky playback in Studio when all was ok in Free

PostPosted: Tue Mar 02, 2021 6:02 pm
by Shrinivas Ramani
A log archive and a project export could help narrow down causes. Please follow these steps when you are about to finish a session (with GPU accelerated decoding disabled) and have a few minutes:

a. at the end of the session, re-enable GPU accelerated decoding.
b. restart Resolve, same project. Play back the same clip for ~20-30 seconds.
c. Stop playback. From the Help menu, create a diagnostic log archive.
d. From the project manager, export the project to a DRP file. You can duplicate the project and remove timelines, isolating just a single clip and a single timeline if there is a privacy concern.
e. In your response, please add a link to these two (DRP and log archive) that engineering can examine. Add some detail on your workflow - source of clip (capture SW/camera model etc), presence of DeckLinks or other monitoring devices, proxies, video capture devices, USB peripherals etc.

Having said that, let's try a couple of other things -
a. is your graphics card inserted in the highest bandwidth PCIe slot?
b. is your monitor connected to the graphics card's display output (and not the onboard graphics)?
c. have you checked if your drivers are manually installed and not Windows DCH? Do consider a clean reinstall (and turning off windows driver overrides) if you're not sure. Point #1 in my post here has a breakdown of what's what.

Re: Jerky playback in Studio when all was ok in Free

PostPosted: Tue Mar 02, 2021 8:39 pm
by Daniel Portillo
Hi, thanks for your help.

I've done another (clean) install of the latest drivers and as you suggested. As far as I can see, the playback is still a bit juddery with the hardware accelerated decoding on.

The GPU is installed in the highest bandwidth PCIe slot and both monitors are connected to it not the onboard monitor outputs.

The material hasn't come from a camera, but it's h264 codec clip. I have no Decklinks or other monitoring/ video capture devices etc. In terms of USB peripherals, it's:

keyboard
trackball mouse
USB 2.0 hub
Contour ShuttleXpress
MPOW Bluetooth dongle
Logitech wireless mouse & dongle
Audient iD14 audio interface
Anker USB 3.0 hub (nothing connected)

Here's a WeTransfer link to the drp and log that you requested:

https://we.tl/t-TEaVOjkrsv

Thanks!

Re: Jerky playback in Studio when all was ok in Free

PostPosted: Tue Mar 02, 2021 9:00 pm
by Daniel Portillo
I just noticed that I'm getting some glitches even with the hardware acceleration switched off. So I'm going to try generating proxy media (DNxHR LB) and comparing the performance with acceleration off/on although by the time the proxy media is in place I'd expect them to both be butter smooth.

Edit:

Doesn't seem like I can generate proxy media for the bunch of subclips that I've been using: I set it off but when done, it seems to have only actually created a proxy for one clip. So presumably I'd have to generate a proxy media file for the whole master clip from which the subclips were made?

Re: Jerky playback in Studio when all was ok in Free

PostPosted: Fri Mar 05, 2021 11:14 am
by Stephen Hay
I am having what sounds like very similar problems with my project, which was working perfectly with 16.2.7 Studio but with 17 Studio I am getting:
1. Frequent freezing of timeline playback when clicking through it, for anything between a couple of seconds and about half a minute. Also, I notice that playback (for 25fps) seems to take a couple of seconds to get up to speed and often reports '26.5' before correcting itself... is this normal?!
2. Flaky intermittent error-failures mid-rendering.
3. Temporary 'Media Offline' mis-reporting.
NVidia 1050Ti is fully updated with clean driver install.
The media is pretty basic - 1080P / 25fps .movs from a Canon 7D which Resolve has always handled without complaint until now.

Re: Jerky playback in Studio when all was ok in Free

PostPosted: Mon Mar 08, 2021 3:26 pm
by Teemu Kyytinen
For me there's sometimes a playback glitch where playback seems to be "forced" on something like 3x speed when pressing either space bar or K. Restart usually fixes the issue. All in all playback has been more jerky with my iMac 5k as well compared to b9 version. My machine is admittedly getting old, but b9 was smoother in my experience when it comes to playback.