Periodic frame stutter when Vsync is enabled with multiple monitors and differing refresh rates

Unity: Graphics Device Features

Won't Fix

6.0.X

2023.3.X

2023.2.X

2023.1.X

2022.3.X

2021.3.X

Hardware limitations mean we can't vsync. Workaround is turn off vsync and use on demand rendering to limit frame rate.

Cancelling this 2023.2 tech release issue since the support for this release has come to end of life. Cancelling this 2023.2 port case does not affect any LTS or Unity 6 Beta/Preview that remain open.

Reproduction steps:
1. Connect three monitors that all are set to different refresh rates (i.e. first is set to higher than 60Hz, second - to 60Hz, third - to lower than 60Hz)
2. Open the attached “FrameDropRepro” project
3. Build and Run the project
4. Observe the frame rate counter in the top right corner of the Player for a few minutes

Expected result: The frame rate never drops below 60 FPS
Actual result: The frame rate occasionally drops below 60 FPS indicating a dropped frame

Reproducible with: 2021.3.27f1, 2022.3.2f1, 2023.1.0f1, 2023.2.0a20

Reproducible on: macOS 13.3 (Intel)

Note: The reproduction is inconsistent and may require waiting for a long time or relaunching the built Player multiple times to reproduce the issue.

Note2: please see the corresponding slack thread here; https://unity.slack.com/archives/C0105CH72UV/p1687367495176459

Periodic frame stutter when Vsync is enabled with multiple monitors and differing refresh rates

Unity: Graphics Device Features

Won't Fix

Prioritise and Follow this issue

Have a workaround or additional info about this issue?

Periodic frame stutter when Vsync is enabled with multiple monitors and differing refresh rates

Unity: Graphics Device Features

Statuses

Won't Fix

Resolution Notes

6.0.XWon't FixHardware limitations mean we can't vsync. Workaround is turn off vsync and use on demand rendering to limit frame rate.

2023.2.XWon't FixCancelling this 2023.2 tech release issue since the support for this release has come to end of life. Cancelling this 2023.2 port case does not affect any LTS or Unity 6 Beta/Preview that remain open.

Description

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Have a workaround or additional info about this issue?