VkResult is VK_SUBOPTIMAL_KHR in Android causing SwapChain to be recreated every frame

[HakimHauston]

swapChain.queuePresent in VulkanExampleBase::submitFrame returns VK_SUBOPTIMAL_KHR in Android.

This causes windowResize() to be called every frame, re-creating the entire swapChain.

What is the cause of this error? And is there a way to prevent this?

Any input is highly appreciated...

[SaschaWillems]

What device does this happen on? I can't replicate this on my Pixel 4a, but I could test with other devices.

And does this happen all the time, or only under certain conditions?

[HakimHauston]

Hi @SaschaWillems

Thanks for the fast reply and willingness to take a look... I am facing the errors on all the devices I've tested with:

• Pixel 6 Pro (Mali-G78 MP20) - Android 14
• Pixel 9 Pro Fold (Mali-G715 MC7) - Android 15 Beta
• OnePlus Open (Adreno 740) - Android 13
• Vivo x90 Pro (Immortalis-G715 MC11) - Android 14

Upon hearing your positive result on Pixel 4a, I grabbed a device and run it but get the same error, this is the screenshot

The error happened all the time, starting from the first frame, I have just sync-ed to the latest commit 1615f95 but this issue also exist in my previous base as early as July (8b4ee59)

[w-pearson]

I noticed this a while ago but never got around to reporting it. It depends on whether the device is held portrait or landscape (I believe the issue happens with landscape, but I'm not 100% sure of this).

VK_SUBOPTIMAL_KHR is generated by Android at https://android.googlesource.com/platform/frameworks/native/+/7a8d900e3d534177284184660cb4c587632bb658/vulkan/libvulkan/swapchain.cpp#2533. https://github.com/KhronosGroup/Vulkan-Samples/tree/main/samples/performance/surface_rotation documents how you can use preTransform to avoid the issue.

[SaschaWillems]

That explains why I don't see this. I usually test in portrait mode. Thanks for the links, will take a look and hopefully fix this :)

[koplas]

I can also reproduce this on my HONOR ALI-NX1. This issue causes performance problems.
I've attached a profile of running the PBRBasic example.

[SaschaWillems]

As noted above: I'm aware of this and will fix it at.

[SaschaWillems]

This might not land for quite some time. It's not easy to adopt an existing code base to this, and I wonder why it has to be so complicated on Android. I might try another route instead, but no promise.

[SaschaWillems]

If someone has time to test: https://github.com/SaschaWillems/Vulkan/tree/pretransform

It's a work-in-progress branch, and e.g. the UI isn't properly rotated yet. But it uses preTransform and at least on my Pixel 9a in landscape mode the submit no longer returns suboptimal.