I'm rendering an project at the moment and I've noticed that computer A and B with nobara 42 and latest nvidia 570..something something drivers is rendering almost twice as fast compared to computer C with rocky linux 9.5 and drivers 550.. something something.

Now after going through deadline render log seems like there is huge difference in preparing scene for render and not in rendering itself, but computer got faster CPU and twice as RAM, all are on 10gig network loading from same NAS.

I was wondering if drivers could be an issue, or I should look more in different direction...

part of deadline log when starting up till render Computer C:
2025-05-26 07:31:57: 0: STDOUT: Load Wall Clock Time: 0:00:14.43
2025-05-26 07:31:57: 0: STDOUT: Update Wall Clock Time: 0:00:13.05
2025-05-26 07:31:57: 0: STDOUT: Load CPU Time: 0:01:20.91
2025-05-26 07:31:57: 0: STDOUT: Load System CPU Time: 0:00:27.68
2025-05-26 07:31:57: 0: STDOUT: Load Memory Usage: 11.90 GB
2025-05-26 07:31:58: 0: STDOUT: 0.0% (1/5, 0.0%) Lap= 0:00:13.26 Left= 1842:03:04 Mem= 12.04 GiB Peak= 12.04 GiB
2025-05-26 07:32:50: 0: STDOUT: First Pixel: 1:06.23
2025-05-26 07:32:55: 0: STDOUT: 0.8% (1/5, 0.2%) Lap= 0:01:10.45 Left= 12:30:22 Mem= 25.55 GiB Peak= 25.55 GiB
2025-05-26 07:33:02: 0: STDOUT: 1.4% (1/5, 0.3%) Lap= 0:01:18.04 Left= 7:54:23 Mem= 25.68 GiB Peak= 25.68 GiB
2025-05-26 07:33:07: 0: STDOUT: 2.0% (1/5, 0.4%) Lap= 0:01:22.19 Left= 5:49:19 Mem= 25.94 GiB Peak= 25.94 GiB
2025-05-26 07:33:14: 0: STDOUT: 2.5% (1/5, 0.5%) Lap= 0:01:29.16 Left= 4:51:09 Mem= 25.94 GiB Peak= 25.94 GiB
2025-05-26 07:33:18: 0: STDOUT: 3.1% (1/5, 0.6%) Lap= 0:01:33.71 Left= 4:08:21 Mem= 25.94 GiB Peak= 25.94 GiB
2025-05-26 07:33:25: 0: STDOUT: 3.7% (1/5, 0.7%) Lap= 0:01:40.19 Left= 3:43:19 Mem= 25.98 GiB Peak= 25.98 GiB
2025-05-26 07:33:29: 0: STDOUT: 4.3% (1/5, 0.9%) Lap= 0:01:45.04 Left= 3:21:58 Mem= 26.03 GiB Peak= 26.03 GiB
2025-05-26 07:33:36: 0: STDOUT: 4.9% (1/5, 1.0%) Lap= 0:01:51.22 Left= 3:07:57 Mem= 26.03 GiB Peak= 26.03 GiB
2025-05-26 07:33:41: 0: STDOUT: 5.5% (1/5, 1.1%) Lap= 0:01:56.38 Left= 2:55:24 Mem= 26.07 GiB Peak= 26.07 GiB
....
2025-05-26 07:48:36: 0: STDOUT: XPU Time Breakdown:
2025-05-26 07:48:36: 0: STDOUT: Category Time
2025-05-26 07:48:36: 0: STDOUT: render_time 0:16:37.45
2025-05-26 07:48:36: 0: STDOUT: XPU Compile Stats:
2025-05-26 07:48:36: 0: STDOUT: Category Stat
2025-05-26 07:48:36: 0: STDOUT: count 0
2025-05-26 07:48:36: 0: STDOUT: max_time 0:00:00
2025-05-26 07:48:36: 0: STDOUT: avg_time 0:00:00
2025-05-26 07:48:36: 0: STDOUT: Total Wall Clock Time: 0:16:53.71
2025-05-26 07:48:36: 0: STDOUT: Total CPU Time: 0:04:13.67
2025-05-26 07:48:36: 0: STDOUT: System CPU Time Only: 0:00:56.85
2025-05-26 07:48:36: 0: STDOUT: Current Memory Usage: 28.09 GiB
2025-05-26 07:48:36: 0: STDOUT: Peak Memory Usage: 28.09 GiB

and computer A:
2025-05-26 08:02:54: 0: STDOUT: Update Wall Clock Time: 0:00:18.99
2025-05-26 08:02:54: 0: STDOUT: Load Wall Clock Time: 0:00:20.60
2025-05-26 08:02:54: 0: STDOUT: Load CPU Time: 0:01:33.39
2025-05-26 08:02:54: 0: STDOUT: Load System CPU Time: 0:00:13.29
2025-05-26 08:02:54: 0: STDOUT: Load Memory Usage: 10.02 GB
2025-05-26 08:02:54: 0: STDOUT: 0.0% (1/5, 0.0%) Lap= 0:00:19.01 Left= 2640:45:42 Mem= 10.17 GiB Peak= 10.17 GiB
2025-05-26 08:04:14: 0: STDOUT: First Pixel: 1:39.24
2025-05-26 08:04:17: 0: STDOUT: 0.8% (1/5, 0.2%) Lap= 0:01:41.67 Left= 18:02:49 Mem= 23.90 GiB Peak= 23.90 GiB
2025-05-26 08:04:21: 0: STDOUT: 1.4% (1/5, 0.3%) Lap= 0:01:46.09 Left= 10:44:55 Mem= 23.90 GiB Peak= 23.90 GiB
2025-05-26 08:04:24: 0: STDOUT: 2.0% (1/5, 0.4%) Lap= 0:01:48.46 Left= 7:40:58 Mem= 24.04 GiB Peak= 24.04 GiB
2025-05-26 08:04:28: 0: STDOUT: 2.5% (1/5, 0.5%) Lap= 0:01:52.96 Left= 6:08:52 Mem= 24.23 GiB Peak= 24.23 GiB
2025-05-26 08:04:32: 0: STDOUT: 3.1% (1/5, 0.6%) Lap= 0:01:56.66 Left= 5:09:10 Mem= 24.23 GiB Peak= 24.23 GiB
2025-05-26 08:04:34: 0: STDOUT: 3.7% (1/5, 0.7%) Lap= 0:01:59.02 Left= 4:25:18 Mem= 24.27 GiB Peak= 24.27 GiB
2025-05-26 08:04:38: 0: STDOUT: 4.3% (1/5, 0.9%) Lap= 0:02:02.82 Left= 3:56:09 Mem= 24.31 GiB Peak= 24.31 GiB
2025-05-26 08:04:40: 0: STDOUT: 4.9% (1/5, 1.0%) Lap= 0:02:05.09 Left= 3:31:24 Mem= 24.39 GiB Peak= 24.39 GiB
2025-05-26 08:04:44: 0: STDOUT: 5.7% (1/5, 1.1%) Lap= 0:02:08.99 Left= 3:07:38 Mem= 24.41 GiB Peak= 24.41 GiB
......
2025-05-26 08:12:33: 0: STDOUT: XPU Time Breakdown:
2025-05-26 08:12:33: 0: STDOUT: Category Time
2025-05-26 08:12:33: 0: STDOUT: render_time 0:09:36.24
2025-05-26 08:12:33: 0: STDOUT: XPU Compile Stats:
2025-05-26 08:12:33: 0: STDOUT: Category Stat
2025-05-26 08:12:33: 0: STDOUT: count 0
2025-05-26 08:12:33: 0: STDOUT: max_time 0:00:00
2025-05-26 08:12:33: 0: STDOUT: avg_time 0:00:00
2025-05-26 08:12:33: 0: STDOUT: Total Wall Clock Time: 0:10:00.30
2025-05-26 08:12:33: 0: STDOUT: Total CPU Time: 0:06:03.78
2025-05-26 08:12:33: 0: STDOUT: System CPU Time Only: 0:01:02.72
2025-05-26 08:12:33: 0: STDOUT: Current Memory Usage: 25.89 GiB
2025-05-26 08:12:33: 0: STDOUT: Peak Memory Usage: 25.89 GiB

Any ideas where to look for a problem?

Are the two computers identical hardware? The speed of the PCIe bus plays a role in GPU computing. Review your motherboard's specs.

slow one is actually my best one, ryzen 5950x 128gb ram, others are threadripper old 1900 and intel 8700 so in all accounts slow machines should be fastest one. I I;ve noticed this only recently as I moved to rocky linux due to wayland incompatibility issues. others are on nobara 42

Booted into windwos, renders fine same as other machines. So my conclusion is most likely older driver, but half the speed. seems a lot.

And confirmed. Managed to get rid of akmod drivers from rpm fusion installed nvidia prop drivers 570 and it is rendering fine now. So anyone on rocky and akmod 550 drivers.. upgrade. loosing half performance otherwise

Nvidia has an official repo for their drivers: https://docs.nvidia.com/cuda/cuda-installation-guide-linux/#network-repo-installation-for-rhel-rocky [docs.nvidia.com]

For RHEL9/Rocky9 it would be: https://developer.download.nvidia.com/compute/cuda/repos/rhel9/x86_64/cuda-rhel9.repo [developer.download.nvidia.com]

Never installed those but with download from their web page and installing but will try that on next sys reinstall. thanks Had rpm fusion with akmod before that... It worked... till I saw diference in rendering on compared. All goodnow