Bug 134631

Summary: LO 7.0 adjusts monitor refresh rate while using Nvidia G-Sync
Product: LibreOffice Reporter: comradenortonwow
Component: LibreOfficeAssignee: Not Assigned <libreoffice-bugs>
Status: RESOLVED NOTOURBUG    
Severity: normal    
Priority: medium    
Version: 7.0.0.1 rc   
Hardware: x86-64 (AMD64)   
OS: Windows (All)   
Whiteboard:
Crash report or crash signature: Regression By:
Bug Depends on:    
Bug Blocks: 129062    

Description comradenortonwow 2020-07-07 21:03:14 UTC 
Description:
When using the 7.0RC1 on Windows 10 along with Nvidia G-Sync set to adjust monitor refresh rate for both windowed and full screen programs the frame rate is reduced to between 25-50 while using the program. This behavior does not exist in 6.4.5.

Steps to Reproduce:
1.Open Libreoffice with G-Sync enabled for both windowed and full screen programs
2.
3.

Actual Results:
Reduced monitor refresh rate while the program is selected.

Expected Results:
Refresh rate stays at its maximum like it does in 6.4.5.


Reproducible: Always


User Profile Reset: No



Additional Info:
Version: 7.0.0.1 (x64)
Build ID: 04ba7e3f1e51af6c5d653e543a620e36719083fd
CPU threads: 12; OS: Windows 10.0 Build 18363; UI render: Skia/Vulkan; VCL: win
Locale: en-US (en_US); UI: en-US
Calc: CL
Comment 1 Luboš Luňák 2020-07-08 11:01:50 UTC 
Why do you think LO is responsible for what some internal nVidia technology does?

This is presumably some interaction between Vulkan and G-Sync. Does forcing Skia to software mode or disabling it altogether in Tools->Options->View change something?
Comment 2 comradenortonwow 2020-07-08 20:01:32 UTC 
(In reply to Luboš Luňák from comment #1)
> Why do you think LO is responsible for what some internal nVidia technology
> does?
> 
> This is presumably some interaction between Vulkan and G-Sync. Does forcing
> Skia to software mode or disabling it altogether in Tools->Options->View
> change something?

I'm not sure if LO is responsible or if it is an Nvidia issue, but I figured I'd report it here because the problem didn't exist in the previous LO version.

When using Shia in software mode the issue does not happen, neither does it happen when Shia is disabled completely.
Comment 3 QA Administrators 2020-07-09 03:42:49 UTC Comment hidden (obsolete)
Comment 4 Luboš Luňák 2020-07-09 10:59:52 UTC 
LO itself doesn't do anything with refresh rate. Possibly this is either a bug in the Skia library, or more likely either in nVidia Vulkan drivers or in nVidia G-Sync. You can try if the problem persists with other Vulkan-capable apps (there's e.g. the 'vkcube' demo app).