This guide explains essential Linux monitoring tools—top, vmstat, pidstat, iostat, netstat, sar, and tcpdump—detailing the metrics they expose, how to interpret CPU, memory, disk, and network statistics, and practical command examples for effective server performance troubleshooting.
Choosing the right file system for a Linux installation can be daunting, so this guide compares the top general‑purpose options—ext4 and Btrfs—while also reviewing alternatives such as ZFS, Reiser4, XFS, and JFS, helping users select the best fit for their needs.
When you need to inspect text files on a Linux system without opening a full editor, these ten command‑line tools—cat, less, head, tail, wc, grep, find, locate, sort, and uniq—provide fast, precise ways to display, search, count, and manipulate file contents.
This article provides a comprehensive guide to Linux Virtual Server (LVS) load balancing, covering its architecture, core concepts, software modules, NAT/TUN/DR modes, scheduling algorithms, ipvsadm command usage, and step‑by‑step deployment of LVS‑NAT with Keepalived for both TCP and UDP scenarios.
This guide explains how to perform CPU stress testing on Linux by installing and using the stress and mpstat commands, detailing installation steps, command options, example executions, and how to interpret their output to assess system performance and stability.
This article explains the VRRP protocol’s core concepts, state machine, election process, and multi‑master HA mode, provides step‑by‑step Linux router configuration examples—including group creation, priority, interface tracking, preempt mode, timers, and learning—plus an overview of Keepalived’s architecture and split‑brain mitigation strategies.
This comprehensive guide explores Linux memory fundamentals, address space layout, fragmentation, the buddy and slab allocation algorithms, kernel and user‑space memory usage scenarios, and common pitfalls, providing backend developers with practical insights to improve performance and stability.
This guide explains how Linux manages file ownership and access rights, covering the use of chown, chgrp, and chmod commands, interpreting symbolic and numeric permission strings, and providing practical examples for changing owners, groups, and permission bits.
From laser cutting and gaming to office tasks, music production, retro computing, and server power, Linux proves it can handle a wide range of unexpected and creative uses beyond traditional desktop or server roles.
This guide explains Linux software installation, comparing pre‑built binary packages with compiling from source, covering package managers, repository formats, build tools like CMake and make, and the advantages of each approach for stability, customization, and access to the latest features.
This comprehensive guide explains Linux memory management concepts, covering physical and virtual memory, allocation and release methods, related kernel functions, process switching interactions, performance tuning, leak detection, fragmentation mitigation, and real‑world application examples with practical C code snippets.
This article explains Linux's multi‑user permission model, describing file type symbols, numeric and symbolic permission representations, and provides practical examples of using chown, chgrp, and chmod to manage file ownership and access rights.
This article introduces a variety of Linux command‑line tools used for stress testing and performance monitoring, covering CPU, memory, disk, network, processes, load, temperature and other utilities with brief usage examples and practical tips.
This article explains how mmap maps file segments into a process's virtual address space, how virtual memory and physical memory interact, and the mechanisms of address translation, paging, and segmentation that enable efficient memory sharing and file I/O in Linux.
This guide introduces 1Panel, an open-source Linux server operation panel that integrates WordPress and Halo, explains how to install it with a single curl command, and demonstrates managing containers, databases, applications, and host settings through its web interface.
This article explains the Linux kernel's transition from bitmap‑based PID allocation to a radix‑tree (IDR) implementation, describes the underlying data structures and code changes, and presents benchmark results showing roughly a 50% performance improvement for common utilities.
Learn how to harness the Linux find command with seven practical examples—including searching by name, type, timestamps, size, permissions, ownership, and executing actions—so you can efficiently locate and manage files, solve common interview questions, and automate system tasks.
This guide explains how rtty combines a lightweight C client, a Go server, and a Vue front‑end to provide web‑accessible terminals for remote Linux device maintenance, covering its key features, installation steps, token generation, and browser‑based access.
This article explains how Linux performance depends on hardware, OS configuration, and application design, detailing CPU, memory, disk I/O, network bandwidth, RAID choices, kernel tuning, file‑system selection, and the roles of operators, architects, and developers in a systematic optimization workflow.
This guide demystifies the Linux filesystem hierarchy by explaining the purpose of each top‑level directory—such as /bin, /etc, /home, /var, and /usr—and shows where different types of files should be stored for a clean, well‑organized system.
This guide explains the differences between binary packages and source code installations on Linux, covering how package managers work, the benefits of pre‑compiled binaries, and when compiling from source can be advantageous.
This guide introduces ten entertaining Linux command‑line tools—rev, asciiview, sl, aafire, cmatrix, factor, oneko, boxes, xeyes, and pv—explaining how to install each package on Debian‑based systems, showing example usage, and illustrating the visual effects with screenshots.
This guide explains how to use tcpdump (and its predecessor ethereal) for capturing and analyzing network traffic, describes key command‑line options, and provides dozens of practical examples ranging from basic packet dumps to complex filtered captures and related networking utilities.
This article explains common reasons why PHP-FPM processes may terminate unexpectedly and provides step‑by‑step instructions for configuring systemd and Supervisor to supervise PHP‑FPM, ensuring continuous and reliable operation on Linux servers.
This guide explains how Linux manages file ownership and access rights, covering the use of chown and chmod commands, interpreting ls -l output, numeric and symbolic permission representations, and practical examples for changing owners, groups, and permission bits.
This article explores common pain points in test development, demonstrates how Shell scripting can automate repetitive Linux tasks, introduces basic commands like copy and concatenate, and presents real‑world case studies such as auto‑comment generation, memory‑usage monitoring, service management, and function encapsulation to boost productivity.
This article explains how to identify and resolve Linux performance bottlenecks by examining hardware resources, operating‑system settings, storage configurations, network bandwidth, and application behavior, and it outlines a systematic troubleshooting workflow for administrators, architects, and developers.
This article shares practical insights from a Linux driver engineer on device trees, cross‑compilation toolchains, filesystem considerations, kernel configuration, and debugging techniques that every newcomer should understand to avoid common pitfalls and integrate drivers successfully.
This guide walks you through the Linux cat command, explaining its basic file‑display function, how to create and append files, redirect content, show line numbers, and remove empty lines, all with clear examples and practical tips for everyday shell use.
Learn how to configure port forwarding on both Windows and Linux servers using netsh and iptables, including commands to view, add, and delete mappings, setting up packet forwarding, and testing the setup with a multi‑machine lab environment.
By adding a guard that skips the costly part‑scan in MergeTreePartsMover::selectPartsForMove when disk usage is below the threshold and no MoveTTL is set, Didi reduced BgMoveProcPool thread CPU consumption from about 30 % to under 4 %, halving overall node CPU load and improving ClickHouse’s PB‑scale performance.
Learn how to install Ansible, then create, modify, and delete crontab entries across multiple hosts using Ansible playbooks, with detailed examples of YAML configurations and command-line instructions that illustrate Infrastructure as Code for reliable scheduled task management.
This guide explains eight practical uses of the ‘!’ operator in Linux shells, covering how to rerun commands by number, reference previous arguments, handle multiple parameters, search by keyword, repeat the last command, and perform conditional deletions and directory checks.
This article explains the Unix pipe operator, demonstrates its convenient usage with practical examples, and then presents a detailed performance benchmark of four different shell methods for calculating string length, showing why excessive piping can significantly reduce script efficiency.
This guide walks you through essential Linux monitoring tools—htop/top for CPU usage, /proc files for hardware details, uptime and sar for load averages, pidstat for per‑process metrics, strace for system calls, lsof for open files, and network utilities like netstat and ss—providing commands, options, and interpretation tips to help you diagnose performance issues efficiently.
Linux perf is a powerful, flexible profiling tool that lets developers and system administrators monitor hardware and software events, analyze CPU, memory, and I/O performance, generate flame graphs, and troubleshoot bottlenecks across single processes, containers, and multi‑core systems, with extensive commands and advanced techniques.
VXLAN (Virtual eXtensible LAN) overcomes VLAN’s 12‑bit limitation by using 24‑bit VNIs, encapsulating Ethernet frames in UDP, and enabling large‑scale, multi‑tenant overlay networks; the article explains its principles, packet format, and provides step‑by‑step Linux kernel and Open vSwitch implementation examples with commands and flow‑table configurations.
This comprehensive guide covers Linux memory management fundamentals, detailing physical and virtual memory concepts, allocation and release mechanisms, key kernel functions, code examples, process switching, performance tuning, leak detection, fragmentation mitigation, and real‑world applications across system, driver, and optimization layers.
This guide outlines eight practical Linux performance‑tuning methods—including kernel parameter tweaks, filesystem and network optimizations, process priority adjustments, memory management, scheduler configuration, software bloat removal, and log cleanup—while showcasing key tools and visual diagrams for effective system optimization.
This article compares popular Linux distributions—Ubuntu and Fedora—examining their package managers, desktop environments, stability, community support, and migration challenges, while also highlighting alternative distros like Bodhi Linux and Linux Lite to help developers choose the most suitable OS for their workflow.
This guide explains Linux serial port device files, shows how to list them, and provides four C programming methods—polling, select‑based interrupt, SIGIO signal handling, and threaded reading—complete with code examples and detailed configuration steps.
This article explains what Linux system calls are, how they are implemented—including parameter preparation, mode switching, execution, and return—and lists common file, process, network, and device calls, highlighting their role in enabling applications to access kernel services.
This article provides a comprehensive reference of common Linux system administration commands, covering system information, date handling, shutdown/reboot, file and directory manipulation, searching, mounting, disk usage, user/group management, permissions, compression, package management, backup, CD/DVD handling, and networking utilities.
Linux 6.4 has been officially released, featuring the removal of SELinux runtime disabling, enhancements to F2FS and Btrfs filesystems, a batch of new Rust code, integration of Intel LAM after criticism, performance optimizations for LoongArch, early Apple M2 support, Wi‑Fi 7, and AMD autonomous boot, while the merge window for 6.5 is now open.
This comprehensive guide explains how to diagnose Linux performance issues using systematic 5W2H analysis, essential monitoring tools for CPU, memory, disk I/O, network, and flame‑graph visualizations, and demonstrates the methodology with a detailed nginx case study to quickly locate bottlenecks.
Mozilla discovered that Firefox crashes on Linux, especially older Debian‑based distributions, whenever users perform an image search on Google; the issue stems from a recent AI‑generated JavaScript function allocating excessive variables, exposing a Linux kernel stack‑limit bug that was fixed in kernel 4.20.
This article explains the structure of Linux Ext (2/3/4) filesystems, detailing superblocks, inode tables and data blocks, then describes block groups, the role of superblocks, and outlines the differences between hardware and software RAID as well as the principles and risks of using LVM for flexible storage management.
Explore the Linux filesystem hierarchy in depth, learning the purpose of each top‑level directory—from /bin and /boot to /var and /usr—and discover where to correctly place different types of files for a clean, well‑organized system.
This article compiles a comprehensive guide to Linux performance analysis, covering essential tools such as vmstat, iostat, dstat, top, htop, pidstat, strace, netstat, lsof, perf and sar, explaining their usage, output interpretation, and how they fit into a systematic performance tuning workflow.
This article explains how Linux manages memory by organizing physical pages, using zones and nodes, allocating memory with the buddy system and SLUB, structuring user and kernel virtual address spaces, and translating virtual addresses to physical ones via page tables, TLBs, and dynamic mapping.
This article explains Linux process creation and termination, covering kernel functions like kernel_thread, kthread_create, kthread_run, the central _do_fork implementation, and user‑space interfaces such as fork, vfork, and pthread_create, with code snippets and diagrams.
This article explains why local DNS caches can cause HTTP errors or DNS spoofing, shows how to view caches created by systemd‑resolved, nscd, and dnsmasq, and provides clear command‑line instructions for flushing those caches on Linux systems, including Chrome’s own DNS cache.
This article explains the distinct roles of the Linux special device files /dev/tty, /dev/tty0, and /dev/console, showing how each maps to the current terminal, the graphical virtual console, and the kernel boot console respectively, with command examples and usage details.
This guide walks you through practical Linux server hardening techniques—including SSH configuration changes, disabling ping responses, managing users and groups, and safely granting root privileges—to significantly reduce the risk of unauthorized access.
This article walks through installing Nginx on CentOS, configuring DNS across three servers, applying common Nginx hardening techniques such as version hiding, log rotation, connection keep‑alive tuning, image caching, and implementing anti‑hotlinking to protect site resources.
This article explains how software performance events in the Linux kernel affect application performance, demonstrates how to list, count, and trace these events with perf, and shows how to visualize the results using FlameGraph to pinpoint bottlenecks such as cache misses, context switches, and page faults.
This article explains the architecture and implementation of the Linux kernel kmalloc memory pool, detailing slab cache creation, size selection rules, cache initialization, allocation and free paths, and how different memory zones are handled, with code examples and diagrams.
This tutorial explains how to configure port forwarding on both Windows (using netsh) and Linux (using iptables), covering query, addition, and deletion of mappings, enabling packet forwarding, and a practical experiment that maps internal services to the external network.
Learn how to stress test a Linux CPU using both a graphical tool (GtkStressTesting) and command‑line utilities (s‑tui and stress), including installation via Flatpak or package managers, configuration steps, monitoring temperature, and exporting results to CSV for analysis.
The article introduces Intel's open‑source monospaced font Intel One Mono, explains its design goals for readability and eye‑protection, shows how to install and compare it with other fonts, and provides a brief guide to creating and using custom fonts on macOS and Linux environments.
This article explains how the Linux kernel supplements its buddy system with the slab allocator to efficiently manage tiny memory blocks, covering slab’s design, memory layout, red‑zone protection, poisoning, per‑CPU caches, NUMA node warehouses, allocation fast‑paths, slow‑paths, and release strategies.
This guide explains why foreground processes terminate when SSH disconnects, introduces signal types SIGINT and SIGHUP, and provides practical methods—including using &, nohup, job control commands, and GNU Screen—to keep Linux tasks running reliably in the background.
Linux processes network packets through a layered TCP/IP stack, starting with hardware DMA into a ring buffer, handling interrupts, traversing the network interface, IP, transport, and application layers on receive, and reversing the flow for sending, with detailed steps for each layer and driver interaction.
The article recounts the evolution of open source from the early days of UNIX and the GNU project to Linux’s rise, highlights Intel’s partnership with Chinese OS communities, and argues that open‑source collaboration and international cooperation are essential for future technological innovation.
This article explains how to detect and block foreign IP addresses from accessing a website by installing the ngx_http_geoip2 module, upgrading Nginx, configuring GeoIP2 databases, updating the Nginx configuration, and verifying the setup with real traffic tests.
This article introduces several powerful Linux command‑line monitoring utilities—including htop, atop, nmon, vtop, bashtop, gtop, and glances—explaining their features, installation commands, and key interactive shortcuts for tracking CPU, memory, disk, and network usage.
Debian 12 “Bookworm” launches with the Linux 6.1 LTS kernel, new non‑free firmware repository, APFS and NTFS tools, updated compilers, expanded architecture support, fresh artwork and fonts, and a five‑year support window, making it the most feature‑rich Debian release yet.
This article explains how Linux kernel drivers use wait queues for process sleep and wake‑up, covering static and dynamic initialization, the various wait_event macros, wake‑up functions, complete driver source code, Makefile setup, and step‑by‑step build and testing instructions.
This guide introduces the vi editor, explains its three operating modes, and provides a comprehensive list of essential shortcuts for navigation, editing, searching, undoing, and saving, helping embedded Linux developers work faster and more efficiently.
This article reviews the fundamentals of eBPF, explains its architecture and tracing mechanisms such as USDT, uprobes, and TC hooks, provides practical code examples, discusses security aspects, and lists notable open‑source projects that leverage eBPF for performance and observability.
This guide walks you through practical Linux commands—tail, head, cat, grep, sed, wc, and pagination tools—to quickly locate, filter, and examine specific error entries within large log files, boosting troubleshooting efficiency for system administrators.
Linux will continue supporting AMD Zen 2 processors and improve performance by optimizing L3 cache usage, while the new select_idle_sibling() patch expands idle‑thread selection beyond the local cache, addressing inefficiencies in the kernel’s load‑balancing on multi‑CCD systems.
This article explains Linux traffic control fundamentals, covering the three-layer processing model, queue types, token‑bucket mechanisms, kernel TC architecture, Qdisc/Class/Filter hierarchy, and provides step‑by‑step tc CLI examples for implementing QoS, DiffServ, and enterprise networking policies.
This article explains the fundamentals of Direct Memory Access (DMA) and Remote Direct Memory Access (RDMA), compares their data transfer mechanisms with traditional networking, and outlines RDMA's advantages, protocols, ecosystem, and real‑world adoption in high‑performance computing and data centers.
This article provides a comprehensive, categorized reference of essential Linux commands covering system information, shutdown, file management, searching, mounting, disk usage, user and group handling, permissions, special attributes, compression, package management, networking, backup, and common utilities, helping users quickly locate and apply the right command in daily operations.
Linus Torvalds announced the Linux 6.4-rc6 kernel, highlighting extensive XFS filesystem fixes, numerous driver updates—including GPU and network drivers—architectural patches for arm64, and a projected stable release around June 25, with a possible delay to July 2 if issues arise.
This guide explains why Docker network IP address conflicts occur, how to diagnose issues such as dockerd failing to start or container ports being unreachable, and provides step‑by‑step solutions including checking logs, adjusting subnet settings, editing daemon.json, and recreating the ingress network to restore normal operation.
This guide explains Linux GPIO fundamentals, driver APIs for requesting, configuring, and reading/writing pins, and demonstrates how to use the pinctrl subsystem with device‑tree examples for both single GPIOs and GPIO arrays.
This tutorial explains how to set up DNS records, install Postfix and Cyrus‑SASL, configure authentication, create necessary configuration files, add users, and test SMTP on an Ubuntu server to reliably send emails without landing in spam folders.
This article presents a curated list of useful Linux command‑line tools—including Nethogs, IOZone, IOTop, IPtraf, IFTop, HTop, NMON, MultiTail, Fail2ban, Tmux, Agedu, NMap and Httperf—along with installation commands and brief usage notes to help system administrators monitor performance, security and resources effectively.
This article explains Linux kernel tracing tools—including kprobes, kretprobes, uprobes, tracepoints, ftrace, perf, and eBPF—detailing how probe handlers are injected, how events are recorded via TraceFS, and which technique best fits different debugging and performance‑analysis scenarios.
This article introduces a collection of essential Linux command‑line tools for stress testing and monitoring system resources such as CPU, memory, disk, network, processes, load, temperature, and other aspects, helping administrators assess stability and performance.
This guide explains what Podman is, how it differs from Docker, and provides step‑by‑step instructions for installing, configuring, and using Podman—including common commands, rootless operation, registry accelerators, volume handling, and essential configuration files—so you can manage containers without a daemon.
This guide explains how to keep Linux programs running after SSH disconnection by using techniques such as appending '&', employing 'nohup' with output redirection, managing jobs with ctrl+z, jobs, bg, fg, and leveraging the 'screen' utility to create detachable sessions.
This article explains the different VXLAN control‑plane options, focuses on the BGP EVPN approach, and provides a step‑by‑step Linux lab using FRR to configure VTEP devices, establish route‑reflector sessions, and verify MAC and FDB propagation across the overlay network.
This guide demystifies the Linux Filesystem Hierarchy Standard by explaining the purpose of each top‑level directory—such as /bin, /etc, /home, /var, and others—and shows where different types of files should be stored for a clean, maintainable system.
This article explains the step‑by‑step process Linux uses to receive and transmit network packets, covering the initialization of the network subsystem, the role of the ring buffer, interrupt handling, and the layered processing through the TCP/IP stack from the NIC up to the application.
This article provides a comprehensive guide to Podman, covering its definition, key differences from Docker, essential CLI commands for containers and images, installation steps, registry accelerators, rootless operation, user namespace handling, volume usage, and configuration files for effective container management on Linux systems.
The second openKylin community board meeting in Beijing detailed governance rules, controlled open‑source initiatives, open‑build infrastructure, innovation projects, ecosystem expansion, and the nomination of new board members, highlighting the community’s rapid growth, extensive SIG groups, and strategic plans for future development.
This article explains Linux process states, how the scheduler puts a running task to sleep with TASK_INTERRUPTIBLE or TASK_UNINTERRUPTIBLE, how wake_up_process() restores TASK_RUNNING, why invalid wakeups occur due to race conditions, and the kernel techniques used to prevent them.
This guide explains how to install iperf on Windows and Linux, configure it for TCP and UDP bandwidth testing, adjust UDP buffer settings, and interpret the resulting performance metrics, providing practical command examples and visual output for accurate network performance analysis.
This guide walks through the essential Linux network utilities—ping, traceroute, and nslookup—detailing their syntax, common options, practical examples, and real‑world scenarios for testing connectivity, tracing routes, and querying DNS records.
This article explores how core Linux ideas—dual‑boot, multi‑architecture support, interchangeable shells, WSL‑like environments, legal battles, distro rivalries, the Unix desktop era, and open‑source philosophy—originated long before Linux, tracing their roots back to early Unix and even earlier computing projects.
This guide explains how to install and configure pyenv on Linux, manage multiple Python versions, use common pyenv commands, resolve typical installation issues, and employ Pipenv to isolate project dependencies, including installation and essential Pipenv commands.
This article traces the evolution of operating‑system level virtualization from the early UNIX chroot to modern Docker containers, explaining the roles of chroot, control groups, various Linux namespaces, their implementation details, and how Docker leverages these mechanisms for isolation and resource management.
This tutorial walks through creating an offline Ceph RPM repository on a ZTE NewStart Linux machine, configuring custom yum sources, installing Ceph, and setting up monitor, OSD, and manager daemons across multiple nodes for a fully functional storage cluster.
This guide explains object storage fundamentals, the bucket model, Ceph's RADOS Gateway (RGW) architecture, step‑by‑step installation (online and offline), configuration, keyring creation, pool setup, troubleshooting PG limits, user creation, and how to access RGW using AWS CLI tools.
This guide explains the Linux ls command, its purpose, and walks through twenty practical options—including long format, human‑readable sizes, sorting, hidden files, recursive listing, and version display—so readers can list and interpret directory contents efficiently.
This article explains what Podman is, highlights its key differences from Docker—including daemon‑less operation and rootless security—covers installation, configuration, common commands for managing containers, images, volumes, and networking, and provides practical examples for using Podman as a Docker‑compatible, cloud‑native container runtime.
This article introduces Podman, an open‑source, daemon‑less container runtime compatible with Docker, explains its architectural differences, rootless operation, configuration files, common commands, image handling, volume usage, and practical tips for Linux environments.
