Do multiple directory imports one by one to prevent seizeups / freezes / crashes

Is there an existing issue for this?

• I checked and did not find my issue in the already reported ones

Describe the bug

I want to import lots of directories at once.
When I start imports on multiple directories the import runs in parallel.
Sometimes this crashes Darktable.

Steps to reproduce

Hard to reproduce but it happens often enough that I normally wait until one import is complete before I start the next.

My files are on a nas so import takes several minutes.
Reproduce: Start import of a directory with hundreds of files; start another one; start another one.
Start browsing around in Darktable. It will soon crash.

The bottleneck is the storage media anyway so it does not go any faster if DT tries to read everything at once.

Expected behavior

Import the files in order. Finish one directory before starting the next. Just like exports.

Logfile | Screenshot | Screencast

No response

Commit

No response

Where did you obtain darktable from?

darktable.org / GitHub release

darktable version

5.1 latest, this has been the case for ... ages

What OS are you using?

Linux

What is the version of your OS?

Linux Mint 22

Describe your system

Linux laptop, fast intel CPU, 32GB ram, raw images stored on a NAS with a 1GB connection.

Are you using OpenCL GPU in darktable?

Yes

If yes, what is the GPU card and driver?

Intel ARK

Please provide additional context if applicable. You can attach files too, but might need to rename to .txt or .zip

No response

Reproduce the crash on Linux Mint with several directory imports running from a NAS while browsing in darktable, as described in the issue. Trace the import workflow and its concurrent activity, then verify that queued directory imports finish one at a time without freezes or crashes.