A professional Linux technology community and learning platform covering the kernel, memory management, process management, file system and I/O, performance tuning, device drivers, virtualization, and cloud computing.
The article explains how replacing the global mmap_lock read lock with per‑VMA locks for madvise MADV_DONTNEED/FREE removes severe lock contention and priority inversion in Linux memory management, and it details the patches, reasoning, and performance evidence supporting the change.
The article details Xavier Xia’s iterative patches to contpte_ptep_get(), showing how early‑exit logic and subsequent refinements consistently improve performance across all tested scenarios without regressions, backed by benchmark data and community discussion.
Qt 6.9 introduces major upgrades across graphics, emoji handling, client‑area APIs, SVG animation, order‑independent transparency, performance optimizations, network authorization, HTTP server security, and developer tools, offering developers a richer, faster, and more secure cross‑platform development experience.
Although HarmonyOS uses a microkernel rather than a monolithic Linux kernel, it achieves Linux compatibility and container emulation through a combination of POSIX support, an ABI shim layer, high‑performance IPC/RPC mechanisms, and the Hardware Driver Framework, which together translate Linux calls into microkernel services.
This article explains how the eBPF verifier checks user‑supplied BPF programs, details register types, instruction encoding, and the verification workflow, and illustrates typical verifier errors with concrete code examples and the exact kernel checks that trigger them.
This 148‑page PPT, created several years ago, offers a thorough summary of virtualization technology—including its fundamentals, hardware‑assisted mechanisms, XEN and KVM architectures, peripheral virtualization, and container/Docker integration—most of which remains relevant today.
This article explains the concept of real‑time operating systems, distinguishes soft and hard real‑time, and walks through Linux kernel factors such as clock tick, interrupt handling, scheduling classes, run‑bandwidth limits, and DPDK polling, providing concrete examples and practical tuning steps.
This article explains the Linux DRM graphics framework, its three main components (libdrm, KMS, GEM), the essential elements for display pipelines, and provides step‑by‑step example programs for single‑buffer, double‑buffer, page‑flip, and plane‑based rendering, including complete source code and execution notes.
This article walks through migrating the USB stack of the STM32‑based candleLight_fw project to HPMicro's cherryUSB, detailing key source files, descriptor conversions, endpoint registration, vendor‑request handling, and showing how four CAN channels are enabled with code snippets and screenshots.
CherryUSB is a compact, highly portable USB host/device protocol stack for embedded systems that offers simplified code, class‑based APIs, extensive class support, low memory footprint, and easy porting across many USB IP cores, backed by detailed documentation and example repositories.
