It turns out the Hierarchical Z "HiZ" implementation with AMD RDNA4 GPUs with the GFX12 graphics engine for early rejection of fragments before hitting the rendering pipeline is slightly buggy. Driver workarounds are needed for the HiZ/HiS support with RDNA4 GPUs to avoid potential hangs.

Following IBM engineers doing a lot of open-source compiler work around a new "arch15" that we suspected to be IBM z17 with Telum II processors, this morning IBM officially announced their next-generation mainframe hardware.

In hoping to ease the experience for Linux enthusiasts and desktop users work through various potential hardware issues when running with AMD Zen (Ryzen) systems on Linux, a new documentation proposal adds a lot of helpers to the Linux kernel documentation area for dealing with different hardware woes.

The Rust-written Redox OS open-source operating system project has published its March 2025 status report that outlines exciting progress made over the past month.

Via Mozilla's Mozilla Builders initiative for fostering open-source AI projects is LocalScore, an interesting local AI large language model (LLM) benchmark for Windows and Linux systems. LocalScore has a lot of potential and also builds off the Mozilla Ocho Llamafile project as an easy-to-distribute LLM framework. LocalScore is still in its early stages but is already working well and will also be used in future hardware reviews on Phoronix.

At the end of March with the Ubuntu 25.04 beta release I began running Ubuntu 25.04 benchmarks on desktop hardware and finding some nice performance improvements thanks to the fresh Linux 6.14 kernel and other new software updates found in this next Ubuntu release. While those numbers were positive, the Ubuntu 25.04 beta performance I am seeing on AMD EPYC 5th Gen "Turin" servers is even more exhilarating. As the first of a lot more Ubuntu 25.04 server benchmarks to come, today is a first look at the Ubuntu 25.04 beta performance on AMD EPYC 9005 compared to Ubuntu 24.10 and the Ubuntu 24.04 LTS releases.

DXVK 2.6.1 was just released as the newest update to this Direct3D 8 / 9 / 10 / 11 over Vulkan API implementation used by Valve's Steam Play (Proton) and other softwarefor enjoying older Windows games on Linux.

For those looking toward a pleasant suspend and resume experience on Ubuntu with the default GNOME desktop, the Ubuntu 25.04 cycle is poised to allow for addressing a five-year-old Ubuntu bug report around the experience. However, for the near-term this is only expected to be in good shape for those using the GNOME X11 session with the GNOME Wayland session requiring further work to the Mutter compositor.

FFmpeg is known for carrying a lot of hand-optimized Assembly code for speeding up this widely-used multimedia library and taking advantage of AVX-512 and other modern CPU ISA capabilities. Merged yesterday was support for making use of AES-NI for those relying on Advanced Encryption Standard (AES) within FFmpeg for encrypted video streams.

When it comes to compiler support for Apple Silicon and their hardware at large, Apple has long been focused on the LLVM/Clang toolchain given their long history with it, employing many of the developers, and Xcode being based on LLVM. The GNU Compiler Collection (GCC) though may soon see upstream support for the newer Apple Cores thanks to the work of GCC developer Iain Sandoe along with the input of engineers from Arm and the Apple open-source team.

For those that prefer waiting for the first point release before upgrading to a new feature release, Linux 6.14.1 was released this morning with an initial collection of fixes atop the Linux 6.14 codebase from two weeks ago.

On Sunday prior to releasing Linux 6.15-rc1, one of the last feature pulls was merging updates for the Turbostat utility that lives within the Linux kernel source tree. The Turbostat tool provides CPU frequency and power statistics along with the ability to query temperatures and other CPU metrics on AMD and Intel processors.

The Linux 6.15 merge window has been capped off with the Linux 6.15-rc1 test kernel having been just released.

As a win for the open-source community from NVIDIA, the company recently announced they are making their PhysX and Flow GPU-accelerated source code open-source.

As we close out the Linux 6.15 merge window this weekend culminating with the Linux 6.15-rc1 release, the input driver updates were merged that include introducing the new Apple Z2 driver.

In addition to the recent optional IO_uring support for the PostgreSQL database server on Linux and async I/O batch mode, another exciting performance improvement was merged this week. Landing in the PostgreSQL database server this week was support for using AVX-512 instructions for CRC32C computations.

One of the early pull requests for Linux 6.15 that I've been meaning to highlight are the VFS iomap updates sent in by Microsoft engineer Christian Brauner. In particular, the VFS iomap pull brings preparations for large atomic writes and its upcoming usage by the XFS and EXT4 file-systems.

Merged a few days ago for the Linux 6.15 kernel were all of the performance events updates for which there are a few notable patches on the AMD and Intel side this cycle.

Among the pull requests coming in at the tail end of the Linux 6.15 merge window with 6.15-rc1 expected tonight are all of the Kbuild updates as the infrastructure for building out the kernel.

The cryptography subsystem updates for the in-development Linux 6.15 merge window are quite exciting with some optimizations for modern x86_64 Intel/AMD processors enticing us the most.