Created attachment 180700 [details] An Archive Of Unprocessed Performance Data After Connection SUMMARY Connecting my smartphone to my PC causes filesystem slowdown for all KDE applications I've tried. That is, Dolphin, Gwenview, and the File Picker KDE Portal (via Gittyup's Flatpak). This behaviour is new. STEPS TO REPRODUCE To reproduce the exact configuration I have (IDK how much applies): 1. Connect a SITECOM CN-386 4-port USB-C hub to the MB's TB4 port. 2. Connect a XAOSUN TB4 cable to the hub. 3. Connect a Fairphone 5 5G to the cable. On my smartphone, I have USB debugging enabled. OBSERVED RESULT Every application which interacts with the filesystem slows to an unreasonable amount. EXPECTED RESULT It shouldn't slow. It never did, until now. SOFTWARE/OS VERSIONS I've explicitly verified that this *affects* `xdg-desktop-portal-kde-6.3.4-2.fc42.x86_64`, `dolphin-25.04.0-3.fc42.x86_64`, and `gwenview-25.04.0-2.fc42.x86_64` (and, strangely, `android-tools-35.0.2-3.fc42.x86_64` and `sudo-1.9.15-7.p5.fc42.x86_64`). The DE and OS are undermentioned: > Operating System: Fedora Linux 42 > KDE Plasma Version: 6.3.4 > KDE Frameworks Version: 6.13.0 > Qt Version: 6.9.0 > Kernel Version: 6.14.3-300.fc42.x86_64 (64-bit) > Graphics Platform: Wayland > Manufacturer: ASRock > Product Name: X670E Taichi I've also verified that this *doesn't* affect `xdg-desktop-portal-gtk-1.15.3-1.fc42.x86_64`. ADDITIONAL INFORMATION I'll add some files with the undermentioned data contained: > . > ├── Flamegraphs > │ ├── bad-adb.avif > │ ├── bad-dolphin.avif > │ ├── bad-gwenview.avif > │ ├── good-adb.avif > │ ├── good-dolphin.avif > │ └── good-gwenview.avif > └── Performance Data > ├── Processed > │ ├── bad-adb.data.perfparser > │ ├── bad-dolphin.data.perfparser > │ ├── bad-gwenview.data.perfparser > │ ├── good-adb.data.perfparser > │ ├── good-dolphin.data.perfparser > │ └── good-gwenview.data.perfparser > └── Unprocessed > ├── bad-adb.data > ├── bad-dolphin.data > ├── bad-gwenview.data > ├── good-adb.data > ├── good-dolphin.data > └── good-gwenview.data > > 5 directories, 18 files This was originally reported at https://discussion.fedoraproject.org/t/connecting-my-smartphone-to-my-pc-via-a-hub-causes-filesystem-slowdown/150633/4?u=rokejulianlockhart#:~:text=:speech_balloon:,a%20hub)%20causes%20filesystem%20slowdown.
Created attachment 180701 [details] An Archive Of Unprocessed Performance Data Before Connection
Created attachment 180702 [details] An Archive Of Processed Performance Data
Created attachment 180703 [details] An Archive Of Flamegraphs
(In reply to Roke Julian Lockhart Beedell from comment #0) The post at Fedora's Discourse instance contains this information and more (BZ can only do so much), including YouTube videos that undeniably demonstrate this problem. Please at least skim it, triage owner.
*** Bug 503427 has been marked as a duplicate of this bug. ***
No idea how to even begin to debug this.
(In reply to Nate Graham from comment #6) I'll keep trying to take a stab at it. I'm damn lucky that it's so consistently reproducible and that the effect is so profound. I'm going to try all kinds of ports and cable combinations next, then try to ascertain whether SystemD slows with the smartphone connected on boot. Per Firefox's apparent unaffectedness, I also need to test more GTK applications that don't support the FreeDesktop File Portal, but they're difficult to locate nowadays.
(In reply to Roke Julian Lockhart Beedell from comment #7) Just like https://github.com/MediaArea/MediaInfo/issues/1111#issuecomment-2853896160, this doesn't appear to reproduce anymore, and I've come to the conclusion that a DLL in `kio-extras` might have caused some system-wide problems, but has now been remediated. It was probably the fault of the distribution, in that case.