Unwanted playback delay before playing animation issue

Support Animation and Rigging
1

Hi guys

I’m working on some simple motion graphics in Blender. I’ve multiple scenes in my file with some deforming planes and animated curves all with simple flat emission shaders.

Often when I press play or shift-space, it takes 3 to 4 seconds for the animation to start playing. Once it plays, everything is fine. This happens about 70% of the time. It doesn’t happen when I play and pause in a short time frame. I guess it’s some sort of caching issue?

Anyone experienced this before?

Intel i7-11800H + RTX A2000 Laptop ; Blender 3.5

2

I would guess that is happening while it is compiling a folder of jpg images to a cache, which facilitates smooth playback. Seems like normal behavior.

3

(I meant just an internal keyframed animation in the viewport, not an imported sequence, in case you misunderstood)

Is that really normal? It’s incredibly annoying and seems odd for an animation this lightweight.

4

Is there a physics sim or something involved that would require it to make a cache?

5

There isn’t. I am using eevee though, so it might be compiled shaders a lot? Doesn’t make much sense, though.

6

Did anyone ever figure this out?

I’m having the same issue on a lenovo laptop equipped with a ryzen 5700H, 64 GB system ram and an rtx 3080 (16 GB dedicated memory) gpu. Basically, after slightly tweaking an animation, there’s a short delay (around 1-2 s) before the animation starts playing. It doesn’t matter whether I’m in eevee material/render preview mode, solid or even wireframe mode - same thing. After the first playback start, the next ones start immediately, unless I change something in the animation, then the delay is back.

I’m on Blender 4.2 now, but I’ve had this problem for almost 2 years, back when using Blender 3.3. I believe.

On my desktop PC I’ve never encountered this issue, working on exactly the same .blend file and using the exact same Blender version - and I do mean exactly the same version - I use it in portable mode, with the same config and addons enabled. So it’s probably not an issue with different Blender settings.

I’m noticing that the OP also encountered the issue on a laptop. So that might be related (though it’s also clear it’s not a, intel vs amd issue, since that’s different between our machines, among other things).

Reinstalling Windows 10 (clean install) didn’t do anything, either. Haven’t tried this on Windows 11, yet.

I tried changing the power setting in windows, too, thinking it has something to do with power optimizations/suspends. Went all the way up to Ultimate Performance mode, disabling everything that was set to turn off after a time. Still no change.

Has anyone encountered the same issue and possibly found a solution?
I’m thinking of reporting this as a bug to Blender Foundation, but I thought I’d check here first. Especially since it seems a complicated one, with all the different hardware combos possible, so I’m not expecting it to be an easy to solve one, and it might just be ignored or closed.