Bug 457228

Summary: Okular is very slow when loading files from sshfs mounts
Product: [Applications] okular Reporter: Massimiliano L <m.lincetto>
Component: generalAssignee: Okular developers <okular-devel>
Status: CONFIRMED ---    
Severity: normal CC: jesiphone2020, kdedev, yvan
Priority: NOR    
Version First Reported In: 21.12.3   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Massimiliano L 2022-07-28 08:17:32 UTC
SUMMARY
When opening a small PDF file (less than 50 KB) on a remote filesystem mounted through sshfs (fuse.sshfs), Okular takes almost 10 seconds to load. The behaviour is the same regardless of the fact Okular is launched from Dolphin or from the command line. Evince for comparison takes less than 2 seconds.

STEPS TO REPRODUCE
1. mount a remote filesystem using sshfs (from the shell)
2. open a PDF file with Okular

OBSERVED RESULT
Okular takes a long time to load (almost 10 seconds).

EXPECTED RESULT
Okular should take a time compatible with other PDF readers.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Ubuntu 22.04
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3
Comment 1 Jonathan E. Snow 2023-11-09 03:41:25 UTC
Confirm, same is true over smb and nfs mounts if latency is >1ms. At 30ms the wait is ~30 seconds for a document to open.