Linux Kernel Journey
This article explains how the built‑in Linux kernel tracer ftrace works, walks through its various tracers, shows how to configure and use it via debugfs, and demonstrates practical performance‑optimisation and fault‑diagnosis scenarios while comparing it with SystemTap and LTTng.
This article explains how KVM/ARM implements split‑mode virtualization by dividing the hypervisor into a lowvisor running in EL2 and a highvisor running in kernel mode, detailing CPU, memory, I/O, interrupt and timer virtualization, and describing the architectural improvements introduced by ARM's Virtualization Host Extensions (VHE).
The article explains a kernel‑space memory profiler that uses a compile‑time code‑tagging library and special linker sections to record allocation callers and byte counts with minimal CPU overhead, allowing the tool to be deployed in production.
The article explains how Type‑1 and Type‑2 hypervisors differ in their use of ARM64 exception levels, outlines their shared responsibilities such as resource, scheduling, and device management, and compares their architectures and performance through a serial‑port example, highlighting the trade‑offs of each approach.
This article provides a detailed, step‑by‑step overview of every Linux interprocess communication mechanism—including pipes, signals, files, semaphores, shared memory, message queues, sockets, and Unix domain sockets—complete with concepts, usage scenarios, diagrams, and full code examples.
The article explains how eBPF‑based sched_ext enables painless design, implementation and deployment of new Linux schedulers, offering faster iteration, better observability, lower entry barriers, and showcases simple FIFO examples, advanced LAVD and rustland schedulers, their adoption in major distros, and performance gains for gaming workloads.
This article walks you through why CMake is a more elegant, cross‑platform alternative to hand‑written Makefiles, explains its core benefits, and provides a complete, hands‑on tutorial that covers the basic workflow, a minimal project example, multi‑source handling, and multi‑directory organization with clear code snippets.
This article explains what ELF files are, details their header, program header table, sections and section header table, and walks through how Linux uses fork and execve to clone a child process and load an ELF binary into a new address space.
This article explains the Linux kernel’s memory management for a process, covering virtual address spaces, page‑fault handling, VMA allocation, stack and heap initialization, sbrk/brk usage, thread‑stack creation, and the glibc ptmalloc heap allocator with concrete code examples and diagrams.
This article explains how to use eBPF and perf events to trace NFS read/write system calls, capture kernel and user stack traces, resolve them to source locations via DWARF, and generate flame‑graph data that is pushed to Pyroscope for performance analysis.
