Have questions? Check out these FAQs for helpful information when working with Vulkan on Arm GPUs.
Q1: What are the common reasons to hit device lost?
A1: A Vulkan application might trigger an out of memory (OOM) condition on Mali GPUs. It results in a DEVICE_LOST error, even if the API usage is correct.
Q2: What is the ‘sub-pass merging feedback’ Vulkan extension?
A2: This extension adds a mechanism to provide feedback to an application about whether the subpasses specified on render pass creation are merged by the implementation.
Q3: What is the ‘control sub-pass function’ Vulkan extension?
A3: This extension introduces a new command which allows developers to query for additional information on GPU faults that may have caused device loss, and to generate binary crash dumps.
Q4: How can I use the debugging extension for Vulkan?
A4: This extension enables applications to track the binding of the GPU virtual address space regions, and to associate those regions with Vulkan objects.
Q5: How can I pick up the most efficient load-store operations?
A5: When you set up your render passes in Vulkan you have to set load and store operations upfront, because it allows for some special optimizations in tile-based GPUs.
Q6: How can I efficiently use Surface Rotation with Vulkan on mobile?
A6: Surface rotation, when you worked with VUlkan, you must take extra care to avoid performance implications. To understand why, we need to start by understanding how display processors work on mobile.
Q7: How to implement descriptor and buffer management with Vulkan?
A7: An application using Vulkan will have to implement a system to manage descriptor sets. The most straightforward and flexible approach is to re-create them for each frame but doing this when targeting mobile platforms can be inefficient and problematic.
Q8: What Arm GPUs support ray-tracing?
A8: Immortalis-G715 adds support for ray-tracing via the VK_KHR_ray_query extension. All current Immortalis GPUs are guaranteed to support ray-tracing.
Q9: What Arm GPUs support descriptor indexing (bindless)?
A9: VK_EXT_descriptor_indexing is supported on all Valhall and 5th Gen GPUs.
Vulkan Mobile Best Practises: FAQs – summary Part-1 blog
It includes: transitioning the swapchain image on acquisition, implicit image transitions via inital Layout / finalLayout, Debugging a DEVICE_LOST, meaning of srcAccessMask =0, Usage of a single image in multiple frames and Using multiple queues.
Vulkan Moble Best Practises: FAQs – summary Part-2 blog
It includes: changing a buffer’s contents dynamically, allocating and mapping memory for a buffer, understanding barrier scope, number of descriptor pools, synchronizing texture transfers, meaning of signalling a fence, struct alignment for uniform buffers and push constants, crashes with no backtrace on Android and shader variants.
