I am running Ubuntu 22.04 and i have never had this happen before. I have been using Ubuntu for over 15 years and I have had my machine freeze up, but never go from fully functioning to hard rebooting.
It happens when I have a large folder open (> 1,500 images) and darktable is trying to generate thumbnails. In settings I have thumbnails and previews writing to disk and being served up via cahce. However, it seems like every time I start up Darktable and go to a familiar folder, It’s working to display thumbnails, anyway. I don’t know if it’s regenerating them, or if it’s just trying to retrieve them from disk.
Anyway, the disk is an SSD and it seems to get the thumbnails reasonable quickly, but now I have this hard rebooting problem. I’ve been trying to keep an eye on my CPU, RAM and temperature and everything has been looking fine. This hard rebooting has happened three times today. Is this something specific to Darktable?
4.6.1, from the official repo, but this morning I was running the 4.5 appimage and switched to try to fix this problem. So both deb and appimage, no snap, no flatpak.
Edit// and I will say that in general, my fan works overtime when I’m trying to navigate through photos in Darktable. This is whether I’m using disk backend or not, xorg or wayland.
Darktable resources are set to ‘medium’. And it says OpenCL is not available for my system, whether in xorg or wayland, and even though I apparently have the opencl packages installed. I’m running an integrated Intel graphics card fwiw.
Just a reminder, -d all is an overkill in most situations, -d pipe is sufficient mostly and -d common would be good if you suspect opencl problems or masks involved.
Thanks for all the thougtful replies. Whether I generate thumbnails from disk or not, it never seems to make a difference. I also set darktable to generate 720p thumbnails in the background, and I can see darktable is using a lot of CPU while idle—and yet, when I scroll through my lighttable, every time I get to a new thumbnail that was below the scoll line, it says ‘working’ and it has to still work to render the thumbnail. I don’t understand it.
edit// I’ll take back that last statement. Eventually, the thumbnails did start loading pretty quickly. But now it seems like darktable is running high CPU all the time. I don’t know if it’s silently running through every film roll or what.
It maybe a coincidence but I am on PopOS 22.04 (Ubuntu based) and I had a catastrophic crash about 2 weeks ago. Hard reboot. Frankly - I don’t know if my DT was even on (I use flatpak).
Depending how aggressive you are with the updates - I tend to check for updates every 1-3 days - it may have been something not related to DT at all - rather related to the update level.
When it comes to a number of images - I usually work with more than 1500 - last time was 2700 (added at once). But I have seen system instability (at least in the past) when I artificially stress the system. In my case was export from DT and simultaneously copying files 30-60 GB. But it was an intentional stress test.
One way to approach it would be ctrl+alt+F3 (to gain terminal). If you can get to it you can kill DT. If DT was the contributor - then it would release the resource and you can go back in with ctrl+alt+F1 (or simply reboot the OS from the terminal) but if you kill DT and the system does not recover - the issue may not be caused by DT at all.
Are you using full screen preview?
Also - DT can be set to generate thumbnails when idle. Maybe this consumes resources.
My first thought is that dust bunnies in the heat sinks will cause the hard rebooting and If the fan is overtiming it, it could be indeed suffering in the cooling dept.
Thanks for all the thoughtful replies. I am leaning toward an overheating CPU as well, but I think this was aggravated by other factors. I switched to Wayland and set thumbnails to generate in the background, and some combination seems to have resolved my problem completely.
I really don’t know what improved, but even importing 200 new images, the thumbnail rendering is lightning fast. This couldn’t be due to background generation because Darktable wasn’t even aware of these images. So I’m guesssing xorg was causing the CPU to overwork, which was overheating my unit (I should also mention I’m using a Dell Micro / USFF machine which is probably meant to perform basic office tasks and not much else)
Thanks so much for all your support, people! I’m impressed by the helpfulness of this community.