mfxlib.log rapidly filling all available diskspace

[johanov]

I have been using OBS 28.1.2 for about 2 years without issues. I few days ago had the program automatically update to the latest version (30). Starting with this update I had a problem with my diskspace filling up until there was no space left when OBS was running. The cause of this was the logfile C:\temp\mfxlib.log which was apparently created by OBS, and was rapidly growing in size independent of whether OBS was recording or not. It had grown to about 130 GB before I found the origin of my disk overflow issues.

Here is a snippet of typical contents;
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 167: D3D11VideoCORE_T<class CommonCORE20>::GetIntelDataPrivateReport: GetVideoDecoderProfile: EXIT
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 144: D3D11VideoCORE_T<class CommonCORE20>::GetIntelDataPrivateReport: D3D11VideoCORE_T<Base>::GetIntelDataPrivateReport: EXIT
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 233: D3D11VideoCORE_T<class CommonCORE20>::IsGuidSupported: D3D11VideoCORE_T<Base>::IsGuidSupported: EXIT
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 233: D3D11VideoCORE_T<class CommonCORE20>::IsGuidSupported: D3D11VideoCORE_T<Base>::IsGuidSupported: ENTER
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 144: D3D11VideoCORE_T<class CommonCORE20>::GetIntelDataPrivateReport: D3D11VideoCORE_T<Base>::GetIntelDataPrivateReport: ENTER
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 156: D3D11VideoCORE_T<class CommonCORE20>::GetIntelDataPrivateReport: GetVideoDecoderProfileCount: ENTER
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 156: D3D11VideoCORE_T<class CommonCORE20>::GetIntelDataPrivateReport: GetVideoDecoderProfileCount: EXIT
D:\qb\workspace\26444\source\sources\mdp_msdk-lib\_studio\shared\src\libmfx_core_d3d11.cpp: 167: D3D11VideoCORE_T<class CommonCORE20>::GetIntelDataPrivateReport: GetVideoDecoderProfile: ENTER

After stopping OBS I could delete the logfile but it was re-created and growing fast as soon as I re-started OBS.

I deinstalled OBS and reinstalled version 28.1.2 i used before and after this the problem was gone. I retained the recording and encoding settings I had used before.

I use OBS on an ACER swift 3 laptop with Windows 11.

 

[koala]

If found a post with that logfile actually referring to Discord:

https://www.reddit.com/r/discordapp/comments/11dyqhe/discord_fills_up_my_ssd_writing_to_mfxliblog_in/

 

[johanov]

I saw that Discord post too but firstly I never did anything with discord and secondly the mfxlib.log file I got was definitely generated by OBS. With OBS running i could not delete it, after closing OBS I could. After reverting to the older version, the log-file did not re-appear.

 

[koala]

Could you post a regular OBS log? May be it's some plugin. You're the first who reports that logfile with OBS, so if this was a regular behavior, we would have seen more reports about it here.

Other posts on reddit or wherever indicate it's connected with a laptop and integrated Intel graphics paired with a Nvidia GPU. Updating the Intel Graphics driver to the most current version fixed the issue for them.

Info from Intel see here:

mfxlib.log file · Issue #3025 · Intel-Media-SDK/MediaSDK

We (Discord) received multiple tickets that very large (hundreds of giga bytes) mfxlib.log file is generated in C:\temp folder. Some users claim that the issue went away after updating driver or us...

github.com

 

[johanov]

Here is the last logfile generated by the OBS version which resulted in the exploding log-file. Before starting OBS I had deleted the mfxlib.log. During the one minute the program was running here, it had generated a new instance of mfxlib.log which had grown to 5903 kB before I stopped the program. During this time i did not record anything. I see now that this was OBS 31.0.1. Version 28.1.2 has now been running for hours and nothing new appeared in C:\Temp.

 

[koala]

Update your Intel graphics driver. You have an older driver than in the linked post from Intel. It's ancient, it's from 2021. A newer one will fix that logfile issue.

 

[johanov]

Driver update indeed solved the problem. After updating OBS to the latest version, the log file no longer appears. According to the Microsoft Device Manager, the driver was up to date and the computer is just two years old. Anyway, things work as they should now. Thanks for your help, Koala.