10 years of front‑line experience at leading firms (Xiaomi, Baidu, Meituan) in development, architecture, and management; discusses technology and life.
This article explains what distributed locks are, outlines their key properties, classifies implementation approaches, and provides detailed walkthroughs of MySQL, Redis, Etcd, and ZooKeeper based locks—including code examples, trade‑offs, and best‑practice recommendations.
The article reviews Didi’s massive November 27‑28 outage, examines reported symptoms, explores likely technical and organizational reasons such as infrastructure failures and cost‑cutting measures, and reflects on the impact of recent layoffs and server‑cost reductions on service reliability.
This article walks through the step‑by‑step evolution of an online supermarket from a simple monolithic web app to a fully split microservice architecture, highlighting the problems encountered, the rationale for each refactoring decision, and the essential components such as service isolation, messaging, monitoring, tracing, gateway, service discovery, circuit breaking, testing, and service mesh.
An Alibaba Cloud outage on November 12, 2023 caused yellow alerts, console and API failures, and service disruptions for Alibaba products such as Taobao, Xianyu, DingTalk, and Yuque, traced to an OSS storage component failure and detailed with a timeline, cause analysis, and personal reflections.
This article walks through the full architecture of a modern bus and subway ticketing platform, covering functional and non‑functional requirements, core components, interaction flows, database schema, shortest‑path routing with Dijkstra, QR‑code generation in Go, and high‑concurrency strategies.
This article sets up a MySQL 5.7 environment, runs a series of SELECT FOR UPDATE queries on primary keys, unique indexes, normal indexes, range scans and non‑indexed columns, then analyzes the resulting lock types—row, gap, next‑key and table locks—and distills practical locking rules.
This article reviews five widely used encryption algorithms—MD5, SHA‑256, DES, AES, and RSA—explaining their classifications, Java implementations, strengths, weaknesses, and how they combine in HTTPS to secure data transmission.
The article explains how Redis’s rich data structures and persistence options enable it to serve not only as a distributed cache but also as a primary store for user profiles, counters, leaderboards, relationships, active‑user tracking, distributed locks, rate limiting, messaging, geospatial queries, and more, while also discussing high‑availability and hot‑cold data challenges.
The article explains what MySQL master‑slave replication lag is, analyzes why it occurs—especially during relay‑log replay and large DDL/DML operations—and provides concrete configuration, hardware, and architectural solutions to reduce or eliminate the delay.
The article shares a veteran programmer’s perspective on navigating a tech career by understanding industry evolution, assessing one’s role with a Google SRE scorecard, strengthening fundamentals, and adopting efficient learning habits to stay relevant amid rapid change.
