AMD PerfOpt Makes it Into Linux 7.4 As A Nice Performance Boost For AMD iGPUs

As anticipated, the AMD PerfOpt feature was picked up for the Linux 7.4 kernel. As shown already in multiple Phoronix benchmarks, AMD PerfOpt makes for a nice performance boost for AMD integrated graphics, especially for AI workloads. The AMD PerfOpt feature allows for iGPUs to bypass the IOMMU when directly accessing system memory. AMD PerfOpt is enabled by default for use with the AMDGPU kernel graphics driver on Radeon integrated graphics systems. I have run performance benchmarks measuring the AMD PerfOpt impact in AMD Boosting AI/LLM Performance For Radeon iGPUs As Much As 18~23% With Linux 7.4 and AMD PerfOpt Boosting Prior-Gen Ryzen APU Performance For AI. Via the dmesg kernel output you can look for "PerfOpt" to verify that it was armed with the AMDGPU driver on your system when running Linux 7.4+. The IOMMU merge landed the support along with some other AMD IOMMU fixes and clean-ups. There is also now Broadcom BCM2712 IOMMU support for the Raspberry Pi 5 display and multimedia devices. Microsoft also contributed a new para-virtualized IOMMU driver for use with Hyper-V.