This article explains the nine GRASP patterns and key object‑oriented design principles—such as Information Expert, Creator, Low Coupling, High Cohesion, Controller, Polymorphism, Pure Fabrication, Indirection, and Protected Variations—showing how they form the foundation for effective software architecture.
JavaScript global variables can be created either explicitly with var or implicitly without it, but only the implicit globals are deletable; this article explains the underlying property descriptor differences, demonstrates delete behavior, and shows how to modify configurability using Object.defineProperty.
This article explains how to automate capacity management focused on application performance, identifies common causes of low resource utilization, proposes safe utilization thresholds, describes a testing framework that uses load‑balancer weighting and real‑time monitoring to pinpoint bottlenecks, and outlines how ops and developers can collaborate to improve efficiency.
This article reviews the evolution of Alibaba's middleware message engine, analyzes the low‑latency and high‑availability challenges faced during Double‑11, and details the optimization techniques, capacity‑guarantee strategies, and HA architecture that enable RocketMQ to handle massive traffic spikes with millisecond‑level latency.
This article explains the iOS message‑sending and forwarding mechanisms—including dynamic, fast, and normal forwarding—and demonstrates how BlocksKit leverages these mechanisms to implement dynamic delegates using blocks, with detailed code examples and class descriptions.
This article explains what an LVS cluster is, outlines its types (LB, HA, HP), details common LVS deployment modes (nat, dr, tun) and their features, describes scheduling algorithms, and provides practical ipvsadm commands and configuration examples for building and managing high‑availability Linux load‑balancing clusters.
This article details a performance comparison of MySQL 5.6.19 and Percona 5.6.25 with and without InnoDB deadlock detection, using sysbench to simulate flash‑sale stock‑decrement scenarios, and shows how turning off deadlock checks and enabling thread‑pool can boost throughput by over a hundred times.
Tencent’s social services cut two hundred million RMB in bandwidth costs by flattening traffic peaks through seven practices—disabling auto‑play, pre‑pushing hot content, compressing media, offering on‑demand quality, using segmented downloads, applying technical breakthroughs like P2P and codec optimization, and filtering illegal content—while preserving user experience.
This guide walks through identifying the root cause of a SQL Server instance's 100% CPU usage using Profiler, analyzing the offending queries, and applying targeted index and query optimizations to dramatically reduce CPU consumption.
This article explains the importance of problem localization for testers, outlines a systematic approach from user interface to database, and provides practical step‑by‑step techniques, case studies, and tips to improve bug detection, communication, and overall software quality.
This article lists the main top‑level directories in a typical Linux filesystem—such as bin, sbin, etc, usr, home, root, dev, lib, mnt, boot, tmp, and var—and explains the purpose of each directory.
This article introduces the GRASP (General Responsibility Assignment Software Patterns) principles, outlines its nine core patterns—including Information Expert, Creator, High Cohesion, Low Coupling, Controller, Polymorphism, Pure Fabrication, Indirection, and Protected Variations—and explains how they guide responsibility assignment, object discovery, and design decisions to achieve high cohesion and low coupling in object‑oriented systems.
The article explains how rapid advances in cloud computing, big data, IoT and artificial intelligence are reshaping business, turning traditional enterprises into data‑driven, intelligent organizations that rely on automated decision‑making and real‑time customer interaction.
Learn how the CSS position property controls element layout, covering static, relative, absolute, fixed, and the modern sticky positioning, their behaviors, usage rules, and browser support, so you can apply the right positioning technique for smooth scrolling effects across browsers.
This article introduces Git as a distributed version‑control system and GitHub as a hosting platform, explains why they are useful, and walks through core commands such as init, add, commit, branch, tag, and push to help developers manage code efficiently and collaborate effectively.
TiDB’s founder Huang Dongxu recounts the journey of building a MySQL‑compatible, distributed database—detailing early challenges, architectural decisions, the extensive testing, the adoption of Go, Rust, Raft, RocksDB, and the emphasis on metrics, cloud‑native design, and open‑source community collaboration.
This article examines the concept, benefits, and practical implementation of A/B testing in iOS development, covering design considerations, code organization patterns such as selector caching, strategy pattern, and protocol dispatchers, as well as related build‑time concerns like static‑library merging and CocoaPods subspecs.
This article explains how Python’s re module implements regular expressions—a powerful, language‑agnostic tool for pattern matching, validation, searching, and text manipulation—covering compilation, core functions, metacharacters, grouping, and practical usage examples.
This article introduces Linux to newcomers, covering its definition as an open‑source operating system, the history of the free‑software movement, practical advantages over Windows, installation basics, compatibility issues, and a detailed comparison with UNIX, highlighting differences in licensing, hardware support, and usage.
This article explains the origins of the Kanban method, clarifies common misconceptions, and outlines its five core practices—visualizing value flow, making policies explicit, limiting work‑in‑progress, managing workflow, and establishing feedback for continuous improvement—highlighting how these practices enhance lean product development.
