Hi,
That’s not the first time I noticed that when I render animation, the frame takes 2 or 3 minutes to reach the sample count, and then it’s stuck like 5 to 10 minutes to save and jump to the next one.
I don’t get why and how to reduce that as it makes me loose so much time on 1’000 frames.
Best.
I’m not sure if it’s actually also stuck here when I render an animation but it sometimes takes terribly long to render the first frame but also the first still image from a queue.
I even have sometimes it happens in real view as well it’s terribly slow on a first load. Exactly like you say, things which use to take like 20 seconds take 5-10 minutes.
If I see the sample rate / second doesn’t looks like what it used to be I reload the scene and often that helps but sometimes I need to reload several times before it acts normal. I even shut down other GPU accelerated software sometimes to see if that makes a difference, so basically all other programs including browsers or browser based things like discord.
@jan.simon.1 I’m not sure if this is a known issue but it’s mentioned by a few others as well. I just don’t have a clue what actually causes it. The same scene can just start normally (also in RT view) but next day it can be a disaster. I’ve the feeling it’s a bit like a priority issue giving the GPU the kick into the right mode but if I look at the frequencies they look normal. For me it happens in both 2025 versions using latest Nvidia driver. If you’ve something I can help testing some things, let me know.
Hi Oscar,
That’s not on the first frame. When I start render the animation, frame saves few second after reaching the sample count. More KS progress in the animation, more the ‘saving’ time increases. If I stop/restart rendering from the last frame rendered, ‘saving’ time is back to normal.
This behavior is on the ‘close render window’ too. If KS had rendered lot of images, closing the rendering window take really long and it’s faster to kill the KS process and relaunch the scene.
Ah check! I still wonder if it actually has to do with the more renders or just some other inconsistent issue, you mention closing the render window takes very long but I sometimes have the same if I just did one single render.
I once had a sequence rendered and it had like 5 renders done every minute but suddenly a render of a single frame took 5 minutes, and the following were also terribly slow. That wasn’t really going up with time but more suddenly. I’ve a topic somewhere about it and the advice was using the suggested Nvidia driver.
It’s just that the specific driver is from September 2024 and I run a lot of software which likes more recent drivers but maybe you can try it and see if it helps. When I installed that driver it did work but it feels a bit like it could be a simple coincidence as well.
I try to take notes if strange things happen but for the sometimes really slow sample rates, I didn’t find any pattern which might cause it.
Hi Oscar,
Thanks for remind me the driver track. I’ll get the 561.09 back and try.
I’ve tried to render my animation in the beta version, and I had similar issue than you, with rendering time of first 30 frames around 5 minutes and then increase up to 3 hours in 2 or 3 frames. Maybe the driver too.
Best.
EDIT: After installing the drivers 561.09, it was worst. GPU crashes at render start and no way to render a simple frame. I went back to the latest, render start again.
I hope the developers will take a look at this. The issue you have sounds bit like some memory leak since it gets worse over time. Too bad the older driver didn’t work for you.
Not sure which version you’re currently using, maybe you can render things in 2024.3 if you still have that one installed. As far as I experienced 2025.x scenes still load in 2024.3 but do give you a warning the scene is created in a newer version. And I can imagine if you use the new planar lights that would give issues.
I think the release of 2025.2 is pretty much around the corner so I hope it will be fixed before release.
Hi,
After digging a bit, I think it could be a network issue more than a KS one. I save pictures directly on network drive and speed transfer between computer <> server seams to decrease with time.
I don’t know why but I’ll try to save images in local drive to test if behaviour is similar.
Best.
Interesting, maybe file a support ticket anyway, I wonder if it could also have to do with the network client of KS. I’ve no experience with the network rendering but I do output mostly to a network drive/server with my renders.
I don’t have actual issues and preferred this since my server automatically creates a backup on another drive. Might change it if I get a new PC since especially Substance Painter files are often huge which is slow on save and loading.
I do notice that while rendering in KS there’s also a lot of network activity and I’m not really sure why since all images are already in VRAM. If you look at task manager, it’s almost like things get loaded again on every frame but not sure if it actually does that.
Hi,
I’m back to this issue as it makes me loose lot of time.
As you can see, time between frames are stable from first (frame 146 _ 22/07/2025 19:59) and after 90 around 22:30, time start to progressivly increase to reach more than an hour.
Scene doesn’t have big differences from start to end with some linear translations/rotations
I noticed 2 differences on the last frames, first, the image sampling time is increasing to reach the 1’200 samples, then, the file saving is incredibly slow too. (10 to 20 Ko/s)
Is there any log that I can check or similar, to help me to find something ?
Did you already had a ticket at support with this issue? I also wonder if your test by saving images locally instead at the network drive has helped.
