Hi there, Is it possible to customize the Metal Performance HUD on Apple TV, similar to how it can be done on iPhone & iPad? Would like to see things like Compiled Shaders for my Apps on tvOS .

If I compile a compute kernel with a call to texture.read(), it fails with the following error: "Error Domain=AGXMetalG13X Code=3 "Encountered unlowered function call to air.get_read_sampler" UserInfo={NSLocalizedDescription=Encountered unlowered function call to air.get_read_sampler}." This error occurs on both macOS and iOS 26 Beta 5, but not when running on a simulator or in a playground. It does not occur on a macOS Sequoia VM. It occurs whether I use the old metal 3 or new metal 4 compilation method. A workaround would be to use a sampler, but according to the feature tables, all platforms support reading from textures of all formats. Below is a minimal example which produces the error: let device = MTLCreateSystemDefaultDevice()! let library = device.makeDefaultLibrary()! let computeFunction = library.makeFunction(name: "compute_test")! do { let pipeline = try device.makeComputePipelineState(function: computeFunction) debugPrint(pipeline) } catch { debugPrint("Metal 3 failed with error:\n\(error)") } #import <metal_stdlib> using namespace metal; kernel void compute_test(uint2 gid [[thread_position_in_grid]], texture2d<float, access::read> in [[texture(0)]], texture2d<float, access::write> out [[texture(1)]]) { out.write(in.read(gid), gid); } I filed feedback FB19530049.

Hi everyone, This project uses PyTorch on an Apple Silicon Mac (M1/M2/etc.), and the goal is to use the MPS backend for GPU acceleration, notes Apple Developer. However, the workflow depends on Float64 (double-precision) floating-point numbers for certain computations, notes PyTorch Forums. The error "Cannot convert a MPS Tensor to float64 dtype as the MPS framework doesn't support float64. Please use float32 instead" has been encountered, notes GitHub. It seems that the MPS backend doesn't currently support Float64 for direct GPU computation. Questions for the community: Are there any known workarounds or best practices for handling Float64-dependent operations when using the MPS backend with PyTorch? For those working with high-precision tasks on Apple Silicon, what strategies are being used to balance performance with the need for Float64? Offloading to the CPU is an option, and it's of interest to know if there are any specific techniques or libraries within the Apple ecosystem that could streamline this process while aiming for optimal performance. Any insights, tips, or experiences would be appreciated. Thanks in advance, Jonaid MacBook Pro M3 Max

We set the CVDisplayLink on macOS to 0 or 120, and get the following. This then clamps maximum refresh to 60Hz on the 120Hz ProMotion display on a MBP M2 Max laptop. How is this not fixed in 4 macOS releases? CoreVideo: currentVBLDelta returned 200000 for display 1 -- ignoring unreasonable value CoreVideo: [0x7fe2fb816020] Bad CurrentVBLDelta for display 1 is zero. defaulting to 60Hz.

Can't seem to get the Metal HUD to display value range's (pre 26 Tahoe). The documented environment variable MTL_HUD_SHOW_VALUE_RANGE doesn't seem to work. https://developer.apple.com/documentation/xcode/monitoring-your-metal-apps-graphics-performance#Display-the-value-range-of-metrics Anyone having any luck?

Hello, Shaders in our application is written using HLSL and we rely on Metal Shader Converter to convert DXIL to Metal IR. We ran into an issue that causes metal pipeline state creation to fail when vertex stage-in function is used on AMD GPUs. Here's the error reported by Metal in Xcode output: Compiler failed with XPC_ERROR_CONNECTION_INTERRUPTED XPC_ERROR_CONNECTION_INTERRUPTED MTLCompiler: Compilation failed with XPC_ERROR_CONNECTION_INTERRUPTED on 4 try. This error suggests an unexpected interruption in the connection. Possible reasons: a crash in the compiler service, termination by the OS due to resource constraints (e.g., jetsam), a timeout in the service, or an issue with IPC. Verify system stability and check the logs for more details. Compiler failed with XPC_ERROR_CONNECTION_INVALID XPC_ERROR_CONNECTION_INVALID MTLCompiler: Compiler encountered XPC_ERROR_CONNECTION_INVALID: failed to check-in, peer may have been unloaded: mach_error=10000003 (is the OS shutting down or process jetsammed?) Compilation failed due to an interrupted connection: XPC_ERROR_CONNECTION_INTERRUPTED. This error occurred after multiple retries. which seems to indicate a internal compiler error. I have a minimal repro here: https://github.com/kcloudy0717/metal_pso_fail/tree/main, simply follow the instructions in README.

I rewrote my graphics pipeline to use Load/Store better for clearing and don't care cases. All my tests pass, and in the Metal debugger, all the draw calls succeed. But when I present drawables (before [commandBuffer commit]) I only get a pink screen. I've tried everything I can think of: making sure the pixel formats are the same for the back buffer as my render targets, etc. But it's still pink. Could you point me in the right direction so I can fix this, or help describe why it's pink. That would be really helpful. Thank you, Brian Hapgood

Hi, I’m using the latest iPad Pro (13-inch) and I can see that Metal offers an rgb10a2unorm texture for rendering, but when I render a grey ramp and measure the actual luminance, I get a pattern that I would expect from an 8-bit texture (see below). Before I start ripping apart all my code, is there anything else I need to do to convince iOS to render my texture in 10-bit? I already tried setting the PixelFormat in my CMetalLayer to rgb10a2unorm, but that didn’t change anything.

Hello, I am quite new to using the metal API and was wondering if it was common (or even possible) if you knew that, when a pipeline was created, you never needed to make another one with the same shaders again, if it is safe to release the library the was used to reference the shaders? Only asking because this is possible in other apis, but apple never mentions (as far as I have found) if this is safe or not safe to do.

The maximumExtendedDynamicRangeColorComponentValue should provide some value between 1.0 and maximumPotentialExtendedDynamicRangeColorComponentValue depending on the available EDR headroom if there is any content on-screen that uses EDR. This works fine in most scenarios but in macOS 26 Tahoe (including in 26.2) this seemingly breaks down when a third party external display is in HDR mode and the Mac goes to sleep and wakes up. After wake only a value of 1.0 is provided by the third party external display's NSScreen object, no matter what (although when the SDR peak brightness is being changed using the brightness slider, didChangeScreenParametersNotification is firing and the system should provide a proper updated headroom value). This makes dynamic tone-mapping that adapts to actual screen brightness impossible. Everything works fine in Sequoia. In Tahoe the user needs to turn off HDR, then go through a sleep/wake cycle and turn HDR back on to have this fixed, which is obviously not a sustainable workaround.

The title is self-exploratory. I wasn't able to find the CAMetalDisplayLink on the most recent metal-cpp release (metal-cpp_macOS15_iOS18-beta). Are there any plans to include it in the next release?

I'm trying to use MTLBinaryArchive. I collected a BinaryArchive from one device and used metal-tt to translate it for all supported iPhone devices, ranging from iPhone 7 Plus to iPhone 16. However, this BinaryArchive is quite large, around 1.5GB uncompressed, and about 500MB compressed in the IPA. I'm wondering how to address the size issue. I watched the WWDC 2022 video, which mentioned that the operating system or app installation process would handle compatibility. Does this compatibility support different GPU chips? I tried installing an IPA with a BinaryArchive collected only from an iPhone 12 on an iPhone 13, but the BinaryArchive didn't take effect. I also saw that Apple supports App Thinning. However, it seems that resources in the Asset Catalog cannot be accessed via URL, and creating an MTLBinaryArchive requires a URL. Is it possible for MTLBinaryArchive to be distributed through App Thinning? The WWDC 2022 video also mentioned using the -Os optimization flag to reduce size. Can this give an estimate of how much compression it would achieve? Are there any methods to solve the BinaryArchive size issue without impacting performance?

Hi, I am working with a large project. We are compiling each material to its own .metallib. They all include many common files full of inline functions. Finally we link it all together at the end with a single big pathtrace kernel. Everything works as expected, however the compile times have gotten completely out of hand and it takes multiple minutes to compile at runtime (to native code). I have gathered that I can do this offline by using metal-tt however if I am wondering if there is a way to reduce the compile times in such a scenario, and how to investigate what the root cause of the problem is. I suspect it could have to do with the fact that every materials metallib contains duplications of all the inline functions. Any ideas on how to profile and debug this? Thanks, Rasmus

Just wondering if anyone knows what it will take to hit greater than 60hz when targeting iPhone. If I set the preferredFramesPerSecond of an MTKView to 120, it works on the iPad, but on iPhone it never goes over 60hz, even with a simple hello triangle sample app... is this a limitation of targeting iPhone?

I am trying to learn the new Metal Peformance Primitives APIs. I have added the MetalPeformancePrimitives framework and included the header in my shader code as per documentation #include <MetalPeformancePrimitives/MetalPeformancePrimitives.h> Unfortunately, Xcode complains that the header cannot be found. How do I include it properly? I am using Xcode 26 on Tahoe. The MetalPeformancePrimitives framework is present on my machine and I can inspect the headers in the filesystem.

I'm updating our app to support metal 4, but the metal 4 types don't seem to get recognized when targeting simulator. Is it known if metal 4 will be supported in the near future, or am I setting up the app wrong?

subj And how in this case are beautiful system dials made with smoke effects and other particles?

Hi, I'm Beginner with Metal 4 and Model I/O 🥺. I can render simple models with just one mesh, but when I try to render models with SubMeshes, nothing shows up on screen. Can anyone help me figure out how to properly render models with multiple submeshes? I think I'm not iterating through them correctly or maybe missing some buffers setup. Here's what I have so far: https://www.icloud.com.cn/iclouddrive/0a6x_NLwlWy-herPocExZ8g3Q#LoadModel

I work on a Qt/QML app that uses Esri Maps SDK for Qt and that is deployed to both Windows and iPads. With a recent iPad OS upgrade to 26.1, many iPad users are reporting the application freezing after panning and/or identifying features in the map. It runs fine for our Windows users. I was able to reproduce this and grabbed the following error messages when the freeze happens: IOGPUMetalError: Caused GPU Address Fault Error (0000000b:kIOGPUCommandBufferCallbackErrorPageFault) IOGPUMetalError: Invalid Resource (00000009:kIOGPUCommandBufferCallbackErrorInvalidResource) Environment: Qt 6.5.4 (Qt for iOS) Esri Maps SDK for Qt 200.3 iPadOS 26.1 Because it appears to be a Metal error, I tried using OpenGL (Qt offers a way to easily set hte target graphics api): QQuickWindow::setGraphicsApi(QSGRendererInterface::GraphicsApi::OpenGL) Which worked! No more freezing. But I'm seeing many posts that OpenGL has been deprecated by Apple. I've seen posts that Apple deprecated OpenGL ES. But it seems to still be available with iPadOS 26.1. If so, will this fix (above) just cause problems with a future iPadOS update? Any other suggestions to address this issue? Upgrading our version of Qt + Esri SDK to the latest version is not an option for us. We are in the process to upgrade the full application, but it is a year or two out. So, we just need a fix to buy us some time for now. Appreciate any thoughts/insights....

Hello, I recently watched the WWDC2025 session titled “Combine Metal 4 machine learning and graphics” (https://developer.apple.com/videos/play/wwdc2025/262/ ), and I’m very excited about the new Metal 4 features that integrate machine learning with graphics—such as neural ambient occlusion, shader-based ML inference, and the use of MTLTensor and MTL4MachineLearningCommandEncoder. While the session includes helpful code snippets and a compelling debug demo (e.g., the neural ambient occlusion example), the implementation details are not fully shown, and I haven’t been able to find a complete, runnable sample project that demonstrates end-to-end integration of ML and rendering in Metal 4. Would Apple be able to provide a full, working example—such as an Xcode project—that shows how to: Export a model to an .mlpackage, Convert it to an .mtlpackage, Use MTL4MachineLearningCommandEncoder alongside render passes, Or embed small neural networks directly in shaders using Shader ML? Having such a sample would greatly help developers like me adopt these powerful new capabilities correctly and efficiently. Thank you very much for your time and support! Best regards,