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The article walks through how to assess MySQL table size, explains why large tables slow down due to B+‑tree index overhead, and compares three practical solutions—table partitioning, database sharding (horizontal, vertical, hash‑range), and hot‑cold archiving—while outlining their trade‑offs and selection criteria.
COUNT(*), COUNT(1) and COUNT(column) may look similar, but they differ in how MySQL processes them, the rows they count, and performance implications, especially with NULL values and index usage; this article explains each form, cites official InnoDB behavior, and guides proper usage.
This article explains how Guava's RateLimiter, built on the token‑bucket algorithm, provides smooth burst handling, configurable rates, warm‑up support, and thread safety, and demonstrates its usage through detailed code examples and best‑practice recommendations for API, database, and crawler throttling.
The article explains how using a large OFFSET with MySQL LIMIT forces the engine to scan and sort hundreds of thousands of index and data pages, then presents three concrete optimizations—covering index scans, subqueries, and partitioned tables—to dramatically reduce the work.
The article walks through six concrete rate‑limiting methods—fixed window, sliding window, leaky bucket, token bucket (Guava RateLimiter), Sentinel middleware, and Spring Cloud Gateway—showing Java implementations, test results, advantages, drawbacks, and how they fit into microservice architectures.
The article explains how to solve interleaved multi‑thread logs in micro‑services by adding a X‑App‑Trace‑Id header, extracting it in a TraceIdFilter, storing it in SLF4J MDC, propagating it through Feign, adapting it for child threads, and finally integrating SkyWalking to print both application and SkyWalking trace IDs in Logback.
This comprehensive tutorial walks through Alibaba Sentinel's core concepts, installation, dashboard setup, microservice integration, flow‑control configurations, degradation strategies, hotspot parameter limiting, system‑adaptive rules, custom block handlers, whitelist/blacklist policies, rule persistence with Nacos, and cluster flow control for resilient Java backend services.
The article explains what a dynamic thread pool is, why static pools are problematic, how to modify core parameters such as corePoolSize, maximumPoolSize, and workQueue at runtime, and provides code examples for monitoring, exposing metrics via Spring Boot Actuator, and integrating with Prometheus‑Grafana, while also listing open‑source implementations like Hippo4j and Dynamic TP.
This article analyses thirteen common mistakes that cause Spring's @Transactional annotation to be ineffective or not roll back, covering unnecessary usage, private/final/static methods, self‑invocation, wrong propagation settings, async threads, unmanaged beans, exception handling and more, with concrete code demos and solutions.
This article presents ten practical MyBatis dynamic‑SQL techniques—including foreach, if, choose, selectKey, trim, and sql fragments—explaining their attributes, common pitfalls, and providing complete Java mapper and XML examples that help reduce boilerplate and avoid errors.
