This article explains how to build a highly configurable, extensible, and maintainable embedded process flow by leveraging Spring AOP and AspectJ to create a lightweight alternative to heavyweight BPM engines, detailing the architecture, design, code examples, and a purchase‑item use case.
This article explains how web instant‑messaging systems achieve reliable, non‑lost and non‑duplicate message delivery by using a six‑message protocol (msg R/A/N and ack R/A/N), timeout‑based retransmission, and deduplication mechanisms.
This article compares two SQL counter queries, presenting a detailed MySQL version with CASE statements and variable counters alongside a concise PostgreSQL version using ROW_NUMBER, and includes an explanation of the differences and a brief author biography.
This article explores how designers creatively repurpose everyday shadows to enhance visual hierarchy, depth, and user experience in user interfaces, illustrating the concept through a series of striking examples that demonstrate practical techniques and design principles.
This article explains the HTTPS protocol, covering its combination of HTTP and TLS, the roles of symmetric and asymmetric encryption, key exchange methods like RSA and ECDHE, certificate-based authentication, data integrity checks, and practical considerations such as performance impact and deployment costs.
The article explains how visualizing both service delivery and service metrics is essential for modern operations, describing the evolution from ITIL processes to DevOps automation, continuous delivery of infrastructure and applications, and data‑driven measurement techniques that enable consistent, agile, and measurable operational performance.
The article analyzes a slow PostgreSQL query that joins multiple tables to fetch flight numbers, compares several alternative query formulations with their execution plans, and presents a final solution using array aggregation to achieve sub‑millisecond performance despite existing indexes.
This article analyzes common push‑service questions, presents a memory‑leak case from an IoT MQTT middleware, and provides detailed Netty design guidelines—including file‑handle limits, CLOSE_WAIT handling, thread and task management, heartbeat tuning, buffer allocation, memory‑pool usage, logging pitfalls, TCP and JVM optimizations—to help engineers build stable, high‑performance million‑connection push servers.
This article examines how to efficiently query PostgreSQL tables that store comma‑separated city names by comparing plain OR conditions, regular‑expression operators, and array‑based searches with GIN indexes, showing speed measurements and validation of result consistency.
With mobile device usage surpassing PC, the article explains why HTML5‑based H5 pages are essential for modern media, compares them to native apps, outlines their technical advantages, and showcases a 3D rotating schedule interface created for the 2014 World Cup as a successful case study.
Replacing a VARCHAR column that stores timestamp strings with a native TIMESTAMP type in a massive sorting table reduced query time from over 20 minutes to 39 seconds, demonstrating a 30‑plus‑fold speedup due to smaller storage, faster CPU comparisons, and reduced I/O.
Disque, an open‑source distributed in‑memory message broker created by Redis's creator, offers synchronous replication, flexible delivery semantics, multi‑master clustering, and fine‑grained job control, but remains in Alpha with several limitations that make it unsuitable for production use today.
The article demonstrates how to split a space‑separated "validperiods" column into separate begin, end, and price fields in PostgreSQL using string_to_array, to_timestamp, regexp_replace, and unnest to transform the data into a readable tabular format.
This article explains the Linux TCP connection‑establishment, packet‑receive, and packet‑send paths, categorizes related kernel parameters such as backlog, SYN‑cookie, ring buffers, and socket buffers, and provides practical commands and guidelines for optimizing network performance on servers.
This article explains why encrypting network traffic is essential, introduces OpenSSL’s cryptographic components, and provides a detailed, command‑line tutorial for creating a private Certificate Authority, issuing certificates, and handling revocation within a LAN environment.
This article explains the fundamentals of DNS, covering its purpose, hierarchical structure, key concepts like FQDN and resource records, query mechanisms, server types, ports, and the step‑by‑step process browsers use to resolve domain names into IP addresses.
The April 25, 2015 Suning Cloud Computing sharing session in Nanjing gathered around 200 cloud enthusiasts and developers, featuring talks on CloudStack’s open‑source contributions, troubleshooting, Docker adoption, object storage practices, custom network design, and distributed storage systems, followed by Q&A and a group photo.
This article explains the concept, implementation details, and practical limitations of Multi‑tenant JVM technology, showing how it enables high‑density Java deployments, improves startup times, and isolates resources and data for multiple tenants within a single JVM instance.
This article explains how to transform a non‑visible 0x03‑separated city string stored in a PostgreSQL table into a sorted array so that routes with the same set of cities can be grouped and counted efficiently.
Learn how to replace traditional backup methods with rsync and inotify for fast, secure, incremental file synchronization, covering rsync fundamentals, command options, server and client configuration, inotify monitoring scripts, and testing procedures to achieve real‑time data replication between Linux servers.
