µVkCompute

µVkCompute is a micro Vulkan compute pipeline and a collection of compute shaders for benchmarking/profiling purposes.

Rationale

Vulkan provides a ubiquitous way to access GPUs by many hardware vendors across different form factors on various platforms. The great reachability not only benefits graphics rendering; it can also be leveraged for general compute, given that Vulkan is both a graphics and compute API.

However, being able to target various GPUs does not mean one size fits all. Developers still needs to understand the characteristics of the target hardware to gain the best utilization. A simple pipeline and a collection of shaders to probe various characteristics of the target hardware often come as handy for the purpose. Thus this repository.

Goals

µVkCompute meant to provide a straightforward compute pipeline to facilitate writing compute shader microbenchmarks. It tries to

Hide Vulkan boilerplate that are required for every Vulkan application, e.g., Vulkan instance and device creation.
Simplify shader resource managemnet, e.g., using reflection over SPIR-V to construct pipeline layouts and compute pipelines.
Provide thin wrapper over command buffer construction and shader dispatch.

µVkCompute focuses more on single compute shader dispatch. µVkCompute does not try to demostrate Vulkan programming best practices. For example, it just uses the system allocator and allocates separate memory for each buffer. Simplicity is favored instead of building a production-level Vulkan application.

Dependencies

This repository requires a common C++ project development environment:

CMake with version >= 3.13
(Optional) the Ninja build system
A C/C++ compiler that supports C11/C++14
Python3

It additionally requires the Vulkan SDK, which will be used for both the Vulkan shared library and shader compilers like glslc for (GLSL) and dxc (for HLSL). Please make sure you have set the VULKAN_SDK environment variable.

Building and Running

Android

git clone https://github.com/google/uVkCompute.git
cd uVkCompute
git submodule update --init

cmake -G Ninja -S ./ -B build-android/  \
  -DCMAKE_TOOLCHAIN_FILE="${ANDROID_NDK?}/build/cmake/android.toolchain.cmake" \
  -DANDROID_ABI="arm64-v8a" -DANDROID_PLATFORM=android-29
cmake --build build-android/

Where ANDROID_NDK is the path to the Android NDK installation. See Android's CMake guide for explanation over ANDROID_ABI and ANROID_PLATFORM.

Afterwards, you can use adb push and adb shell to run the benchmark binaries generated into the build-android/ directory on Android devices. For example, for a benchmark binary bench at build-android/benchmarks/foo/bar/bench:

# Push the benchmark to the Android device
adb push build-android/benchmarks/foo/bar/bench /data/local/tmp
adb shell "cd /data/local/tmp && ./bench"

Note that for Android 10, if you see the "Failed to match any benchmarks against regex: ." error message, it means that no Vulkan ICDs (a.k.a., Vulkan vendor drivers) are discovered. This is a known issue that is fixed in Android 11. A workaround is to copy the Vulkan ICD (normally as /vendor/lib[64]/hw/vulkan.*.so) to /data/local/tmp and run the benchmark binary with LD_LIBRARY_PATH=/data/local/tmp.

Linux/macOS

git clone https://github.com/google/uVkCompute.git
cd uVkCompute
git submodule update --init

cmake -G Ninja -S ./ -B build/
cmake --build build/

Afterwards you can run the benchmark binaries generated into the build/ directory on the host machine.

Windows

git clone https://github.com/google/uVkCompute.git
cd uVkCompute
git submodule update --init

cmake -G "Visual Studio 16 2019" -A x64 -S ./ -B build/
cmake --build build/