Designing a Scalable Lottery System: Stock Pre‑allocation, Real‑time Risk Control & Dynamic Probability

This article details the design of a reusable, configurable lottery platform for a youth‑focused social app, covering business background, pain points, a modular data model, micro‑service architecture, stock pre‑allocation with optimistic and distributed locks, real‑time risk detection, over‑issue prevention, probability calculation, and future AI‑driven enhancements.

Backend ArchitectureLottery Systemdistributed locking

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Designing a Scalable Lottery System: Stock Pre‑allocation, Real‑time Risk Control & Dynamic Probability

Architecture Breakthrough

Aug 5, 2022 · Backend Development

Designing Reliable Scheduled Tasks for Multi‑Instance Java Applications

This article explains how to design and implement reliable scheduled tasks in multi‑instance Java applications, covering task types, clustering solutions like Quartz, lock strategies, version‑based data consistency, and key operational considerations such as intervals, priorities, and monitoring.

Multi-InstanceScheduled Tasksbackend design

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Designing Reliable Scheduled Tasks for Multi‑Instance Java Applications

Java Interview Crash Guide

Nov 28, 2021 · Backend Development

Why Quartz Jobs Were Duplicated and How to Fix It

This article analyzes a Quartz 2.3.0 job‑scheduling issue where millions of daily triggers caused occasional duplicate executions, explains the underlying lock mechanisms and state transitions, and provides a simple configuration change to prevent the problem in distributed environments.

Job SchedulingQuartzdebugging

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Why Quartz Jobs Were Duplicated and How to Fix It

Java Tech Enthusiast

Aug 7, 2021 · Backend Development

Cache Optimization and Distributed Locking in High-Concurrency Systems

By illustrating how to replace simple HashMap caching with Redis‑based distributed caches and locks—using SETNX, Lua scripts, and Redisson—the article shows Spring Boot developers how to prevent cache breakdown, ensure data consistency, and dramatically improve throughput in high‑concurrency web applications.

Cache ConsistencyDistributed SystemsLoad Testing

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Cache Optimization and Distributed Locking in High-Concurrency Systems