Bug 445585

Summary:	Dolphin should be able to identify a CIFS mount point as remote and behave accordingly (very slow directory browsing performance is possible)
Product:	[Applications] dolphin	Reporter:	Mike <legacy5k>
Component:	view-engine: details mode	Assignee:	Dolphin Bug Assignee <dolphin-bugs-null>
Status:	RESOLVED NOT A BUG
Severity:	normal	CC:	kfm-devel, legacy5k, nate
Priority:	NOR
Version:	20.12.3
Target Milestone:	---
Platform:	Kubuntu
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Mike 2021-11-16 12:51:56 UTC

SUMMARY
***
Dolphin seems to browse a CIFS mounted remote filesystem as if it were local, which means that directory contents will be summarized in the "Size" column causing a potentially massive performance hit.
***

STEPS TO REPRODUCE
1. Mount a SMB share as CIFS to your system.  Preferably some directory in the share contains a huge number of files or dirs... in my case one dir has about 5,000 subdirs which really causes a dramatic performance impact.
2. Browse to the mounted dir in Dolphin using "Details" view mode.
3. Dolphin may become unresponsive for up to 10 seconds as the default behavior is that it's counting the number of items inside the directories which takes a long time from an SMB source.  Even changing the Size column to display file sizes for dirs causes some impact.
4. Now browse to the same location but instead of using CIFS mounted path, use "smb://" protocol path.
5. Same directories will display lightning fast because it is not populating the "Size" column with information.

OBSERVED RESULT

Dolphin can become unresponsive as it is apparently not recognizing a CIFS mount as a remote filesystem.

EXPECTED RESULT

Dolphin should recognize that the CIFS mount is a remote source, and employ the same behavior as when browsing "smb://" path for instance, allowing lightning fast performance.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Kubuntu 21.04
KDE Plasma Version: 5.21.4
KDE Frameworks Version: 5.80.0
Qt Version: 5.15.2

Comment 1 Nate Graham 2021-11-23 20:04:35 UTC

> Dolphin can become unresponsive as it is apparently not recognizing a CIFS mount as a remote filesystem.
Yes, that's what happens when you mount a remote network share as a local directory. This is one of many reasons why doing so is a bad idea.

A better solution is to use the system's built-in features rather than fighting them. This means:
1. Make sure kio-fuse is installed. If it's not, install it and bug your distro to install it by default.
2. When you need to access a share, access it in Dolphin using the Network browser or its URL. If you access the share frequently, make a bookmark using its URL rather than manually mounting it somewhere.
3. When you want to open a file on the share, do so using Dolphin when dolphin is showing the share at its remote network path, not a local mount.
4. When you want to open a file on the share from an app that's already open, use the file dialog and access it from the bookmark you added earlier.

Basically don't fight the system. Then everything should work much better. :)