Bug 506521

Summary:	KRDP Memory Usage Filling System RAM
Product:	[Plasma] KRdp	Reporter:	Nicholas Clewer <nick.clewer>
Component:	general	Assignee:	Unassigned bugs <unassigned-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	crash	CC:	ahiemstra, jackyzy823, sitter
Priority:	NOR
Version First Reported In:	6.4.2
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	System Info Screenshot Flamegraph Export Hotspot Parser File Heaptrack of krdpserver

Description Nicholas Clewer 2025-07-03 06:11:15 UTC

Created attachment 182886 [details]
System Info Screenshot

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SUMMARY
When connected to KRDP session from Windows RDP client, KRDP application uses system ram until full. Disconnecting RDP session stops usage but does not let it go (ram).


STEPS TO REPRODUCE
1. Install of KRDP
2. Add user to KDE KRDP settings
3. Enable KRDP
4. Connect to host using Windows RDP Client
5. Log into system
6. Monitor system ram usage increase, more updates on screen faster ram fills.


OBSERVED RESULT
System RAM is used until Kernel closes RDP session due to memory usage and kills KRDP pid, freeing up memory.

EXPECTED RESULT
KRDP should not keep increasing RAM usage.

SOFTWARE/OS VERSIONS
Windows: Windows 11 Pro 23H2
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Arch Linux Kernel 6.15.4-arch2-1 (64bit)
KDE Plasma Version: 6.4.2
KDE Frameworks Version: 6.15.0 
Qt Version: 6.9.1

ADDITIONAL INFORMATION
Graphics Platform: Wayland
Running in Proxmox 8.3.4 VM (4 x vCPU, 6GB vRAM)

Comment 1 Harald Sitter 2025-07-03 15:43:11 UTC

I tried all sorts of things but I can't reproduce this on master.

Could you maybe try to run krdpserver through hotspot https://github.com/KDAB/hotspot and upload the recording or a screenshot of the flamegraph for inspection.

Comment 2 Nicholas Clewer 2025-07-04 01:23:23 UTC

Created attachment 182924 [details]
Flamegraph Export

Flamegraph image of process during issue

Comment 3 Nicholas Clewer 2025-07-04 01:24:47 UTC

Created attachment 182925 [details]
Hotspot Parser File

Export of Hotspot Parser during issue

Comment 4 Nicholas Clewer 2025-07-04 01:27:07 UTC

Video capture of issue, logging into host with Windows 11 RDP Client.
Memory ticks up faster with more screen activity till kernel kills process.
https://youtu.be/0YPL46OJM8A

Comment 5 Harald Sitter 2025-07-04 15:28:35 UTC

Oh sorry! I am a muppet. Hotspot is for cpu usage analysis, we'll want the data from running heaptrack https://invent.kde.org/sdk/heaptrack 😅

Comment 6 Nicholas Clewer 2025-07-09 23:53:05 UTC

Created attachment 183112 [details]
Heaptrack of krdpserver

Added Heaptrack

Comment 7 Harald Sitter 2025-07-10 07:01:09 UTC

Yeah that pretty much looks like a leak in mesa not our code.

You appear to be missing debug symbols though. Could you do another recording but first run

debuginfod-find debuginfo /usr/lib/libgallium-25.1.4-arch1.2.so

to fetch the debug symbols. I hope that works anyway

Comment 8 Bug Janitor Service 2025-07-25 03:46:50 UTC

🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!

Comment 9 Bug Janitor Service 2025-08-09 03:46:54 UTC

🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.

Comment 10 jackyzy823 2025-09-27 04:26:36 UTC

Hi , i also encountered the same memory leak bug of krdp under  llvmpipe (non 3d  acceleration under VM).  

After searching , i came here from the post https://forum.endeavouros.com/t/krdp-memory-leak-oom/75156

The bug won't happened on virgl and softpipe. this makes me recall bug 507746 

So I think the root cause is the same as bug 507746  .   mesa's implementation of dmabuf in llvmpipe has some bugs.

and after applying patch from https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37088  and testing with krdp, i think it is fixed .

 (however not as the version 25.2.3 mentioned in https://forum.endeavouros.com/t/krdp-memory-leak-oom/75156 , i think this patch will be included in 25.3.0)