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GMThttps://blog.zoloy.top/posts/redis-cluster-gossip%E5%8D%8F%E8%AE%AE/https://blog.zoloy.top/posts/redis-cluster-gossip%E5%8D%8F%E8%AE%AE/深入解析 Redis Cluster 基于 Gossip 的去中心化节点发现与故障检测机制，涵盖 PING/PONG 交换、PFAIL/FAIL 两级判定与 16384 槽位设计。Sat, 07 Mar 2026 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-dledger-raft/https://blog.zoloy.top/posts/rocketmq-dledger-raft/解析 RocketMQ DLedger 如何将 Raft 共识协议嵌入 CommitLog 写入路径，以多数派提交替代异步复制实现自动故障切换，以及为什么 ConsumeQueue 不参与 Raft 同步。Thu, 05 Mar 2026 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%8F%8C%E4%BA%B2%E5%A7%94%E6%B4%BE%E6%9C%BA%E5%88%B6/https://blog.zoloy.top/posts/%E5%8F%8C%E4%BA%B2%E5%A7%94%E6%B4%BE%E6%9C%BA%E5%88%B6/双亲委派机制自底向上检查、自顶向下加载，保证核心类不被篡改，是 Java 类加载安全的基石。Mon, 02 Mar 2026 09:00:00 GMThttps://blog.zoloy.top/posts/%E4%B8%AD%E6%96%AD%E6%9C%BA%E5%88%B6%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/%E4%B8%AD%E6%96%AD%E6%9C%BA%E5%88%B6%E8%AF%A6%E8%A7%A3/从硬件信号到内核处理的全链路：中断控制器、IDT、保存现场、中断处理函数、恢复返回，完整覆盖中断处理流程。Sat, 28 Feb 2026 09:00:00 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GMThttps://blog.zoloy.top/posts/%E5%BC%82%E6%AD%A5%E5%8C%96%E6%94%B9%E9%80%A0%E9%82%AE%E4%BB%B6%E5%8F%91%E9%80%81/https://blog.zoloy.top/posts/%E5%BC%82%E6%AD%A5%E5%8C%96%E6%94%B9%E9%80%A0%E9%82%AE%E4%BB%B6%E5%8F%91%E9%80%81/将邮件发送从主线程剥离为异步执行，配合线程池配置与持久化保障，实现用户体验从 2 秒到 50ms 的飞跃。Wed, 18 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%9C%88%E5%A4%8D%E6%9D%82%E5%BA%A6-mccabe%E5%85%AC%E5%BC%8F/https://blog.zoloy.top/posts/%E5%9C%88%E5%A4%8D%E6%9D%82%E5%BA%A6-mccabe%E5%85%AC%E5%BC%8F/圈复杂度用 McCabe 公式（V=E-N+2P）量化代码的独立路径数，为重构提供数学依据，指导函数拆分与测试用例设计。Sun, 15 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/%E4%B9%90%E8%A7%82%E9%94%81%E4%B8%8E%E6%82%B2%E8%A7%82%E9%94%81/https://blog.zoloy.top/posts/%E4%B9%90%E8%A7%82%E9%94%81%E4%B8%8E%E6%82%B2%E8%A7%82%E9%94%81/乐观锁用 CAS/版本号以无锁方式应对低冲突场景，悲观锁用数据库行锁保证强一致性，理解两种世界观的选择依据。Fri, 13 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/segmented%E5%88%86%E6%AE%B5%E9%94%81%E4%BC%98%E5%8C%96/https://blog.zoloy.top/posts/segmented%E5%88%86%E6%AE%B5%E9%94%81%E4%BC%98%E5%8C%96/从秒杀库存扣减到 10 倍并发提升——分段锁将全局资源按 userId 分片，不同分段的操作完全并行，配合段间迁移补偿与死锁防护，思想在 ConcurrentHashMap、LongAdder 中均可见。Tue, 10 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/resttemplate%E8%BF%9E%E6%8E%A5%E6%B1%A0%E4%BC%98%E5%8C%96/https://blog.zoloy.top/posts/resttemplate%E8%BF%9E%E6%8E%A5%E6%B1%A0%E4%BC%98%E5%8C%96/揭示 RestTemplate 默认构造器的性能黑洞——每次 HTTP 请求新建 TCP 连接，详解 HttpComponentsClientHttpRequestFactory 连接池化的完整生产级配置。Sun, 08 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/nginx-vs-tomcat/https://blog.zoloy.top/posts/nginx-vs-tomcat/Nginx(C 语言反向代理零拷贝静态资源)与 Tomcat(Java Servlet 容器业务引擎)分工明确，黄金组合各司其职不可互相替代Fri, 06 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/java-aio-io_uring-%E7%9C%9F%E6%AD%A3%E5%BC%82%E6%AD%A5io/https://blog.zoloy.top/posts/java-aio-io_uring-%E7%9C%9F%E6%AD%A3%E5%BC%82%E6%AD%A5io/同步非阻塞与异步根本区别在谁负责读数据到用户缓冲区，Java AIO 在 Linux 底层用 epoll 模拟，io_uring 通过共享环形队列实现真正内核异步 IO。Tue, 03 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/jmeter%E5%8E%8B%E6%B5%8B%E6%96%B9%E6%B3%95%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/jmeter%E5%8E%8B%E6%B5%8B%E6%96%B9%E6%B3%95%E8%AF%A6%E8%A7%A3/QPS 是 HTTP 层请求数 TPS 是业务事务数二者不可混用，看 P99 而非 Average 才能发现长尾延迟，渐进式加压找到拐点比最高 QPS 更有意义。Sun, 01 Feb 2026 09:00:00 GMThttps://blog.zoloy.top/posts/jdbc%E6%89%B9%E9%87%8F%E6%8F%92%E5%85%A5%E4%BC%98%E5%8C%96/https://blog.zoloy.top/posts/jdbc%E6%89%B9%E9%87%8F%E6%8F%92%E5%85%A5%E4%BC%98%E5%8C%96/JDBC 批量插入核心优化链：executeBatch 减少网络往返 30 倍，加 rewriteBatchedStatements=true 合并 SQL 解析再提速至 100 倍。Thu, 29 Jan 2026 09:00:00 GMThttps://blog.zoloy.top/posts/hikari%E8%BF%9E%E6%8E%A5%E6%B1%A0%E4%BC%98%E5%8C%96%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/hikari%E8%BF%9E%E6%8E%A5%E6%B1%A0%E4%BC%98%E5%8C%96%E8%AF%A6%E8%A7%A3/HikariCP 以无锁 ConcurrentBag 加速连接借还，maximum-pool-size 遵循 CPU 核数×2+磁盘数公式，max-lifetime 须小于数据库 wait_timeout。Tue, 27 Jan 2026 09:00:00 GMThttps://blog.zoloy.top/posts/consul%E6%9C%8D%E5%8A%A1%E6%B3%A8%E5%86%8C%E4%B8%8E%E5%8F%91%E7%8E%B0/https://blog.zoloy.top/posts/consul%E6%9C%8D%E5%8A%A1%E6%B3%A8%E5%86%8C%E4%B8%8E%E5%8F%91%E7%8E%B0/Consul 通过服务注册、Agent 健康检查自动摘除故障节点、consul-template 动态渲染 Nginx 配置，实现微服务无感扩缩容。Sat, 24 Jan 2026 09:00:00 GMThttps://blog.zoloy.top/posts/%E9%9D%A2%E8%AF%95%E4%BF%A1%E6%81%AF%E5%AF%86%E5%BA%A6-%E5%9B%9E%E7%AD%94%E7%AD%96%E7%95%A5/https://blog.zoloy.top/posts/%E9%9D%A2%E8%AF%95%E4%BF%A1%E6%81%AF%E5%AF%86%E5%BA%A6-%E5%9B%9E%E7%AD%94%E7%AD%96%E7%95%A5/面试回答采用先结论后细节的策略，将 80%的细节留给面试官追问，用钩子引导对话进入自己准备的领域。Thu, 22 Jan 2026 09:00:00 GMThttps://blog.zoloy.top/posts/%E7%AE%97%E6%B3%95%E9%9D%A2%E8%AF%95%E5%BF%83%E6%99%BA%E6%A8%A1%E5%9E%8B/https://blog.zoloy.top/posts/%E7%AE%97%E6%B3%95%E9%9D%A2%E8%AF%95%E5%BF%83%E6%99%BA%E6%A8%A1%E5%9E%8B/算法面试三步法：先说暴力解展现理解，再分析瓶颈定位方向，最后优化到最优并分析复杂度。Mon, 19 Jan 2026 09:00:00 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GMThttps://blog.zoloy.top/posts/%E9%9D%A2%E8%AF%95%E5%9B%9E%E7%AD%94%E6%A1%86%E6%9E%B6-%E4%B8%83%E8%A6%81%E7%B4%A0%E4%B8%8E%E4%B8%89%E7%89%88%E6%9C%AC/https://blog.zoloy.top/posts/%E9%9D%A2%E8%AF%95%E5%9B%9E%E7%AD%94%E6%A1%86%E6%9E%B6-%E4%B8%83%E8%A6%81%E7%B4%A0%E4%B8%8E%E4%B8%89%E7%89%88%E6%9C%AC/一套统一的面试回答框架：项目/实习用七要素（结论→背景→目标→难点→取舍→行动→复盘），知识类用三版本（30秒一句话/2分钟核心/5-10分钟深入），并对照 STAR 与系统设计四步法说明来龙去脉。Mon, 10 Nov 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E6%8A%80%E5%B7%A7%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E6%8A%80%E5%B7%A7%E7%AF%87/技巧五题：只出现一次的数字位运算、多数元素摩尔投票、颜色分类三路快排、下一个排列、寻找重复数。Fri, 07 Nov 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%A4%9A%E7%BB%B4%E5%8A%A8%E6%80%81%E8%A7%84%E5%88%92%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%A4%9A%E7%BB%B4%E5%8A%A8%E6%80%81%E8%A7%84%E5%88%92%E7%AF%87/多维动态规划五题：不同路径、最小路径和、最长回文子串、最长公共子序列、编辑距离。Tue, 04 Nov 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%8A%A8%E6%80%81%E8%A7%84%E5%88%92%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%8A%A8%E6%80%81%E8%A7%84%E5%88%92%E7%AF%87/动态规划九题：爬楼梯、打家劫舍、零钱兑换、单词拆分、最长递增子序列、乘积最大子数组、分割等和子集、最长有效括号。Sat, 01 Nov 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E8%B4%AA%E5%BF%83%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E8%B4%AA%E5%BF%83%E7%AF%87/贪心四题：买卖股票一次交易、跳跃游戏与跳跃游戏 II、划分字母区间维护最后出现位置。Wed, 29 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%A0%86%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%A0%86%E7%AF%87/堆三题：第 K 大元素用最小堆、前 K 高频元素堆加哈希计数、数据流中位数用大小顶堆。Sun, 26 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E6%A0%88%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E6%A0%88%E7%AF%87/栈五题：有效的括号、最小栈、字符串解码、每日温度单调栈、柱状图中最大的矩形单调栈。Thu, 23 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E4%BA%8C%E5%88%86%E6%9F%A5%E6%89%BE%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E4%BA%8C%E5%88%86%E6%9F%A5%E6%89%BE%E7%AF%87/二分查找六题：搜索插入位置、二维矩阵、找首尾位置、搜索旋转数组、找最小值、两个正序数组的中位数。Mon, 20 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%9B%9E%E6%BA%AF%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%9B%9E%E6%BA%AF%E7%AF%87/回溯八题：全排列与子集的选择撤销、组合总和剪枝、括号生成、单词搜索、分割回文串、N 皇后。Fri, 17 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%9B%BE%E8%AE%BA%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%9B%BE%E8%AE%BA%E7%AF%87/图论四题：岛屿数量 DFS 淹没、腐烂橘子多源 BFS、课程表拓扑排序判环、实现 Trie 前缀树。Tue, 14 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E4%BA%8C%E5%8F%89%E6%A0%91%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E4%BA%8C%E5%8F%89%E6%A0%91%E7%AF%87/二叉树十五题：中序与层序遍历、最大深度与直径、验证 BST、前中序构造、最近公共祖先、最大路径和。Sat, 11 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%AD%97%E6%AF%8D%E5%BC%82%E4%BD%8D%E8%AF%8D%E5%88%86%E7%BB%84-hashmap%E6%A8%A1%E5%BC%8F/https://blog.zoloy.top/posts/%E5%AD%97%E6%AF%8D%E5%BC%82%E4%BD%8D%E8%AF%8D%E5%88%86%E7%BB%84-hashmap%E6%A8%A1%E5%BC%8F/利用规范表示作为 HashMap 的 key，将字母异位词归为等价类，揭示分组问题的通用模式。Fri, 10 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E9%93%BE%E8%A1%A8%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E9%93%BE%E8%A1%A8%E7%AF%87/链表十四题：三指针反转、dummy 节点合并、Floyd 快慢指针判环、K 个一组翻转、归并排序链表、LRU 缓存。Wed, 08 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%90%88%E5%B9%B6k%E4%B8%AA%E5%8D%87%E5%BA%8F%E9%93%BE%E8%A1%A8/https://blog.zoloy.top/posts/%E5%90%88%E5%B9%B6k%E4%B8%AA%E5%8D%87%E5%BA%8F%E9%93%BE%E8%A1%A8/合并 K 个升序链表的两大解法：小顶堆每次取 K 个链表的当前最小头节点，分治法两两归并逐步合并，时间复杂度对比分析。Wed, 08 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E7%9F%A9%E9%98%B5%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E7%9F%A9%E9%98%B5%E7%AF%87/矩阵四题：矩阵置零首行首列标记、螺旋矩阵按层遍历、旋转图像转置加翻转、搜索二维矩阵 II 从左下角起步。Sun, 05 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%8D%95%E8%B0%83%E6%A0%88%E4%B8%8E%E6%BB%91%E5%8A%A8%E7%AA%97%E5%8F%A3%E6%9C%80%E5%A4%A7%E5%80%BC/https://blog.zoloy.top/posts/%E5%8D%95%E8%B0%83%E6%A0%88%E4%B8%8E%E6%BB%91%E5%8A%A8%E7%AA%97%E5%8F%A3%E6%9C%80%E5%A4%A7%E5%80%BC/单调栈维护有序性解决下一个更大元素问题，单调队列维护时效性解决滑动窗口最大值，有序性与时效性的经典博弈。Sun, 05 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%8A%A8%E6%80%81%E8%A7%84%E5%88%92%E6%A0%B8%E5%BF%83%E6%80%9D%E6%83%B3/https://blog.zoloy.top/posts/%E5%8A%A8%E6%80%81%E8%A7%84%E5%88%92%E6%A0%B8%E5%BF%83%E6%80%9D%E6%83%B3/动态规划两大要素——最优子结构与重叠子问题，通过状态定义和转移方程将指数级递归转化为多项式级递推求解。Fri, 03 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E6%99%AE%E9%80%9A%E6%95%B0%E7%BB%84%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E6%99%AE%E9%80%9A%E6%95%B0%E7%BB%84%E7%AF%87/普通数组五题：最大子数组和 Kadane、合并区间排序、轮转数组三次反转、除自身乘积前后缀、缺失正数原地哈希。Thu, 02 Oct 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%89%8D%E7%BC%80%E5%92%8C%E4%B8%8E%E5%93%88%E5%B8%8C%E8%A1%A8/https://blog.zoloy.top/posts/%E5%89%8D%E7%BC%80%E5%92%8C%E4%B8%8E%E5%93%88%E5%B8%8C%E8%A1%A8/前缀和将子数组求和转化为两数之差，配合哈希表将 O(n²)降为 O(n)，是子数组和类问题的万能解题模板。Tue, 30 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%AD%90%E4%B8%B2%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%AD%90%E4%B8%B2%E7%AF%87/子串三题：和为 K 用前缀和哈希、滑动窗口最大值用单调队列、最小覆盖子串用双指针收缩。Mon, 29 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E4%BA%8C%E7%BB%B4%E6%95%B0%E7%BB%84%E5%8E%9F%E5%9C%B0%E5%93%88%E5%B8%8C/https://blog.zoloy.top/posts/%E4%BA%8C%E7%BB%B4%E6%95%B0%E7%BB%84%E5%8E%9F%E5%9C%B0%E5%93%88%E5%B8%8C/把数组本身当哈希表，利用下标与值的映射关系原地标记状态，实现 O(1)空间解决缺失正整数等经典问题。Sun, 28 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E6%BB%91%E5%8A%A8%E7%AA%97%E5%8F%A3%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E6%BB%91%E5%8A%A8%E7%AA%97%E5%8F%A3%E7%AF%87/滑动窗口两题：无重复字符最长子串用 Set 收缩窗口、字母异位词用固定窗口计数比对。Fri, 26 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E4%BA%8C%E5%8F%89%E6%A0%91%E9%81%8D%E5%8E%86%E6%A8%A1%E6%9D%BF-%E5%89%8D%E4%B8%AD%E5%90%8E%E5%B1%82%E5%BA%8F/https://blog.zoloy.top/posts/%E4%BA%8C%E5%8F%89%E6%A0%91%E9%81%8D%E5%8E%86%E6%A8%A1%E6%9D%BF-%E5%89%8D%E4%B8%AD%E5%90%8E%E5%B1%82%E5%BA%8F/前中后层序四种遍历的递归与迭代统一模板，前中后只是访问根节点的时机不同，层序用队列逐层处理。Thu, 25 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%8F%8C%E6%8C%87%E9%92%88%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%8F%8C%E6%8C%87%E9%92%88%E7%AF%87/双指针四题：移动零快慢指针、盛水容器相向收缩、三数之和排序去重、接雨水按列求和。Tue, 23 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E4%BA%8C%E5%88%86%E6%9F%A5%E6%89%BE-%E5%8F%98%E4%BD%93%E6%A8%A1%E6%9D%BF/https://blog.zoloy.top/posts/%E4%BA%8C%E5%88%86%E6%9F%A5%E6%89%BE-%E5%8F%98%E4%BD%93%E6%A8%A1%E6%9D%BF/二分查找核心在于区间定义（左闭右闭/左闭右开），掌握 8 种变体模板统一解决查找等于、第一个、最后一个等场景。Tue, 23 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/leetcode-%E5%93%88%E5%B8%8C%E7%AF%87/https://blog.zoloy.top/posts/leetcode-%E5%93%88%E5%B8%8C%E7%AF%87/哈希表三题：两数之和 O(1) 补数查询、字母异位词分组排序作 key、最长连续序列用 Set 去重。Sat, 20 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/lru%E7%BC%93%E5%AD%98-hashmap-%E5%8F%8C%E5%90%91%E9%93%BE%E8%A1%A8/https://blog.zoloy.top/posts/lru%E7%BC%93%E5%AD%98-hashmap-%E5%8F%8C%E5%90%91%E9%93%BE%E8%A1%A8/HashMap 快速查找+双向链表维护访问顺序，实现 O(1)级 LRU 缓存淘汰，虚拟头尾节点简化边界操作Thu, 18 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/kadane%E7%AE%97%E6%B3%95-%E6%9C%80%E5%A4%A7%E5%AD%90%E6%95%B0%E7%BB%84%E5%92%8C/https://blog.zoloy.top/posts/kadane%E7%AE%97%E6%B3%95-%E6%9C%80%E5%A4%A7%E5%AD%90%E6%95%B0%E7%BB%84%E5%92%8C/Kadane 算法 O(n)单遍历解最大子数组和，curSum<0 时丢弃负数前缀重新开始，核心 dp[i]=max(nums[i],dp[i-1]+nums[i])Mon, 15 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/floyd-%E5%BF%AB%E6%85%A2%E6%8C%87%E9%92%88-%E7%8E%AF%E6%A3%80%E6%B5%8B/https://blog.zoloy.top/posts/floyd-%E5%BF%AB%E6%85%A2%E6%8C%87%E9%92%88-%E7%8E%AF%E6%A3%80%E6%B5%8B/快慢指针每步缩小距离 1 保证环内必相遇，相遇后等速从表头和相遇点出发在环入口重逢，由数学推导 a=(n-1)L+c 保证正确性。Sat, 13 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/bfs-dfs%E7%AE%97%E6%B3%95%E6%A8%A1%E6%9D%BF/https://blog.zoloy.top/posts/bfs-dfs%E7%AE%97%E6%B3%95%E6%A8%A1%E6%9D%BF/BFS 层序遍历中每轮队列 size 计数是区分层级的关键，DFS 回溯枚举所有路径，两种模板覆盖所有图遍历场景。Thu, 11 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%BE%93%E5%85%A5url%E5%88%B0%E9%A1%B5%E9%9D%A2%E5%B1%95%E7%A4%BA%E5%85%A8%E6%B5%81%E7%A8%8B/https://blog.zoloy.top/posts/%E8%BE%93%E5%85%A5url%E5%88%B0%E9%A1%B5%E9%9D%A2%E5%B1%95%E7%A4%BA%E5%85%A8%E6%B5%81%E7%A8%8B/从 URL 输入到页面展示经历 DNS、TCP、TLS、HTTP、解析渲染七个阶段，每个阶段都有对应的性能优化策略。Mon, 08 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E7%BD%91%E9%A1%B5%E6%85%A2%E8%BD%AC%E5%9C%88%E6%8E%92%E6%9F%A5/https://blog.zoloy.top/posts/%E7%BD%91%E9%A1%B5%E6%85%A2%E8%BD%AC%E5%9C%88%E6%8E%92%E6%9F%A5/从物理层到应用层的六层网页慢排查体系，先定位 TTFB 还是 Content Download，再逐层排障。Sat, 06 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E6%9C%8D%E5%8A%A1%E7%AB%AF%E6%AD%A3%E5%B8%B8%E5%90%AF%E5%8A%A8%E4%BD%86%E5%AE%A2%E6%88%B7%E7%AB%AF%E8%AF%B7%E6%B1%82%E4%B8%8D%E5%88%B0/https://blog.zoloy.top/posts/%E6%9C%8D%E5%8A%A1%E7%AB%AF%E6%AD%A3%E5%B8%B8%E5%90%AF%E5%8A%A8%E4%BD%86%E5%AE%A2%E6%88%B7%E7%AB%AF%E8%AF%B7%E6%B1%82%E4%B8%8D%E5%88%B0/从 ping 到 telnet 到防火墙到监听地址的六层可达性排查清单，覆盖 90%的服务连不上问题。Wed, 03 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E6%9C%8D%E5%8A%A1%E7%AB%AF%E5%A4%A7%E9%87%8Ftime_wait%E5%8E%9F%E5%9B%A0/https://blog.zoloy.top/posts/%E6%9C%8D%E5%8A%A1%E7%AB%AF%E5%A4%A7%E9%87%8Ftime_wait%E5%8E%9F%E5%9B%A0/TIME_WAIT 本质是 TCP 可靠关闭的副作用，解决关键在于减少连接创建销毁频率，而非盲目调整内核参数。Mon, 01 Sep 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E4%B8%BA%E4%BB%80%E4%B9%88%E5%9B%9B%E6%AC%A1%E6%8C%A5%E6%89%8B%E8%A6%81%E7%AD%892msl/https://blog.zoloy.top/posts/%E4%B8%BA%E4%BB%80%E4%B9%88%E5%9B%9B%E6%AC%A1%E6%8C%A5%E6%89%8B%E8%A6%81%E7%AD%892msl/TIME_WAIT 等待 2MSL 的两大原因：确保最后的 ACK 被对端接收，及让旧连接的迷途报文在网络中彻底消失。Fri, 29 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E4%B8%BA%E4%BB%80%E4%B9%88%E5%9B%9B%E6%AC%A1%E6%8C%A5%E6%89%8B%E4%B8%AD%E9%97%B4%E4%B8%A4%E6%AC%A1%E4%B8%8D%E8%83%BD%E5%90%88%E5%B9%B6/https://blog.zoloy.top/posts/%E4%B8%BA%E4%BB%80%E4%B9%88%E5%9B%9B%E6%AC%A1%E6%8C%A5%E6%89%8B%E4%B8%AD%E9%97%B4%E4%B8%A4%E6%AC%A1%E4%B8%8D%E8%83%BD%E5%90%88%E5%B9%B6/TCP 全双工通信决定了被动关闭方的 ACK 和 FIN 代表不同语义，中间两次不能合并，深入理解数据发送与关闭的独立性。Wed, 27 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/tcp%E7%B2%98%E5%8C%85%E4%B8%89%E7%A7%8D%E8%A7%A3%E5%86%B3%E6%96%B9%E6%A1%88/https://blog.zoloy.top/posts/tcp%E7%B2%98%E5%8C%85%E4%B8%89%E7%A7%8D%E8%A7%A3%E5%86%B3%E6%96%B9%E6%A1%88/TCP 字节流没有消息边界，详解粘包根因及固定长度、分隔符、长度字段三种应用层解决方案与 Netty 实现。Sun, 24 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/tcp%E6%8B%A5%E5%A1%9E%E6%8E%A7%E5%88%B6/https://blog.zoloy.top/posts/tcp%E6%8B%A5%E5%A1%9E%E6%8E%A7%E5%88%B6/从慢启动到 BBR，详解 TCP 拥塞控制四大算法的状态迁移及 AIMD 动态调整拥塞窗口的核心思想。Fri, 22 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/tcp%E5%9B%9B%E6%AC%A1%E6%8C%A5%E6%89%8B/https://blog.zoloy.top/posts/tcp%E5%9B%9B%E6%AC%A1%E6%8C%A5%E6%89%8B/深入解析 TCP 四次挥手全过程及 TIME_WAIT 状态的产生原因，理解主动关闭方为何需要等待 2MSL。Tue, 19 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/tcp%E4%B8%8Eudp%E5%8C%BA%E5%88%AB/https://blog.zoloy.top/posts/tcp%E4%B8%8Eudp%E5%8C%BA%E5%88%AB/TCP 面向可靠，UDP 追求速度，深刻理解传输层两种设计哲学的取舍及 QUIC 的演进方向。Sun, 17 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/tcp%E4%B8%89%E6%AC%A1%E6%8F%A1%E6%89%8B/https://blog.zoloy.top/posts/tcp%E4%B8%89%E6%AC%A1%E6%8F%A1%E6%89%8B/论证 TCP 为什么三次握手刚好——两次不足以防止历史重复连接，四次没必要因为 SYN+ACK 可合并，三次精确满足双方确认收发能力+同步初始序列号+防旧连接干扰。Thu, 14 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/tcp-syn-flood-syncookies/https://blog.zoloy.top/posts/tcp-syn-flood-syncookies/解析 SYN Flood 攻击原理——利用三次握手不对称性以极小成本打满半连接队列，syncookies 将连接状态编码进 ISN 序列号实现无状态防御，优雅地将存储开销转为计算开销。Tue, 12 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/sql%E6%B3%A8%E5%85%A5-xss-csrf/https://blog.zoloy.top/posts/sql%E6%B3%A8%E5%85%A5-xss-csrf/梳理 Web 安全三大经典攻击的原理与防御——SQL 注入用参数化查询防代码拼接，XSS 靠输出编码+CSP+HttpOnly，CSRF 用 Token+SameSite Cookie 阻断跨站伪造。Sat, 09 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/osi%E4%B8%83%E5%B1%82%E6%A8%A1%E5%9E%8B%E4%B8%8Etcp-ip%E5%9B%9B%E5%B1%82%E6%A8%A1%E5%9E%8B/https://blog.zoloy.top/posts/osi%E4%B8%83%E5%B1%82%E6%A8%A1%E5%9E%8B%E4%B8%8Etcp-ip%E5%9B%9B%E5%B1%82%E6%A8%A1%E5%9E%8B/OSI 七层是理论蓝图先有模型后有协议，TCP/IP 四层是工程事实标准先有协议后有模型，分层思想使各层独立演进互不影响Thu, 07 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/nginx%E8%B4%9F%E8%BD%BD%E5%9D%87%E8%A1%A1-5%E7%A7%8D%E7%AE%97%E6%B3%95/https://blog.zoloy.top/posts/nginx%E8%B4%9F%E8%BD%BD%E5%9D%87%E8%A1%A1-5%E7%A7%8D%E7%AE%97%E6%B3%95/Nginx 五种负载均衡算法：轮询、加权轮询平滑算法避免打桩、IP 哈希保持会话、URL 一致性哈希最小化缓存失效、最短时间商业版Tue, 05 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/http%E9%95%BF%E8%BF%9E%E6%8E%A5-websocket/https://blog.zoloy.top/posts/http%E9%95%BF%E8%BF%9E%E6%8E%A5-websocket/HTTP 长连接只是复用 TCP 一问一答仍是半双工，WebSocket 通过 HTTP Upgrade 握手将 TCP 升级为全双工帧协议实现双向实时推送。Sat, 02 Aug 2025 09:00:00 GMThttps://blog.zoloy.top/posts/http%E7%8A%B6%E6%80%81%E7%A0%81-%E6%96%B9%E6%B3%95%E8%AF%AD%E4%B9%89/https://blog.zoloy.top/posts/http%E7%8A%B6%E6%80%81%E7%A0%81-%E6%96%B9%E6%B3%95%E8%AF%AD%E4%B9%89/301 永久重定向浏览器缓存 SEO 权重传递，302 临时重定向每次回源；502 是上游无效响应，504 是上游超时无响应。Thu, 31 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/https%E6%8F%A1%E6%89%8B%E8%BF%87%E7%A8%8B/https://blog.zoloy.top/posts/https%E6%8F%A1%E6%89%8B%E8%BF%87%E7%A8%8B/TLS 1.2 用三个随机数协商会话密钥，ECDHE 临时密钥对实现前向安全，TLS 1.3 砍掉 RSA 精简为 1-RTT 并强制前向安全。Mon, 28 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/http2-http3-quic/https://blog.zoloy.top/posts/http2-http3-quic/HTTP/2 多路复用解决 HTTP 层队头阻塞但受 TCP 层拖累，HTTP/3 基于 QUIC 让每个 Stream 独立重传彻底根除队头阻塞。Sat, 26 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/http-vs-rpc/https://blog.zoloy.top/posts/http-vs-rpc/HTTP 面向资源通用性强适合对外 API，RPC 面向方法高性能强类型适合内部微服务，网关层用 REST 内部用 gRPC 各取所长。Wed, 23 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/dns%E5%9F%9F%E5%90%8D%E8%A7%A3%E6%9E%90/https://blog.zoloy.top/posts/dns%E5%9F%9F%E5%90%8D%E8%A7%A3%E6%9E%90/DNS 是分布式树状数据库，解析从浏览器缓存到 hosts 到递归查询根/TLD/权威服务器逐级查找，多级缓存使 90% 查询在本地完成。Mon, 21 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/dns-over-tcp-vs-udp/https://blog.zoloy.top/posts/dns-over-tcp-vs-udp/DNS 选 UDP 因其无连接 1-RTT 延迟、无状态低资源消耗完美匹配海量小查询模式，应用层超时重传加缓存补偿可靠性。Fri, 18 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/ddos%E6%94%BB%E5%87%BB%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/ddos%E6%94%BB%E5%87%BB%E8%AF%A6%E8%A7%A3/DDoS 是不对称资源消耗战：SYN Flood 半连接耗尽、UDP 反射放大、HTTP Flood 伪装正常请求，防御需 CDN 分散加流量清洗纵深体系。Wed, 16 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/cookie-session-jwt/https://blog.zoloy.top/posts/cookie-session-jwt/Cookie 是传输载体，Session 存服务端可主动销毁，JWT 自包含无状态验签适合分布式，三者配合使用形成完整鉴权体系。Sun, 13 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E9%A1%B5%E9%9D%A2%E7%BD%AE%E6%8D%A2%E7%AE%97%E6%B3%95-lru-clock/https://blog.zoloy.top/posts/%E9%A1%B5%E9%9D%A2%E7%BD%AE%E6%8D%A2%E7%AE%97%E6%B3%95-lru-clock/从 OPT 的理论下界到 Clock 的工程实现，Clock 算法用硬件访问位和环形指针以 O(1)复杂度近似 LRU 效果。Fri, 11 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E9%9B%B6%E6%8B%B7%E8%B4%9D%E5%8E%9F%E7%90%86/https://blog.zoloy.top/posts/%E9%9B%B6%E6%8B%B7%E8%B4%9D%E5%8E%9F%E7%90%86/零拷贝通过 sendfile 让数据从 Page Cache 直接到网卡，避免用户态中转，Kafka 吞吐量因此提升一倍。Tue, 08 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%BF%9B%E7%A8%8B%E9%97%B4%E9%80%9A%E8%AE%AFipc%E5%85%A8%E8%A7%88/https://blog.zoloy.top/posts/%E8%BF%9B%E7%A8%8B%E9%97%B4%E9%80%9A%E8%AE%AFipc%E5%85%A8%E8%A7%88/七种 IPC 方式按数据传输模式分为消息传递型、共享内存型和同步型，选型核心取决于数据量和通讯模式。Sun, 06 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%BF%9B%E7%A8%8B%E8%B0%83%E5%BA%A6%E7%AE%97%E6%B3%95%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/%E8%BF%9B%E7%A8%8B%E8%B0%83%E5%BA%A6%E7%AE%97%E6%B3%95%E8%AF%A6%E8%A7%A3/从 FCFS 到多级反馈队列的六种调度算法演进，MLFQ 通过边运行边学习的动态优先级实现通用系统的最佳调度。Thu, 03 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%BF%9B%E7%A8%8B%E7%BA%BF%E7%A8%8B%E5%8D%8F%E7%A8%8B%E7%9A%84%E6%9C%AC%E8%B4%A8%E5%8C%BA%E5%88%AB/https://blog.zoloy.top/posts/%E8%BF%9B%E7%A8%8B%E7%BA%BF%E7%A8%8B%E5%8D%8F%E7%A8%8B%E7%9A%84%E6%9C%AC%E8%B4%A8%E5%8C%BA%E5%88%AB/进程是资源分配的最小单位，线程是 CPU 调度的最小单位，协程在用户态调度实现极致轻量的并发模型。Tue, 01 Jul 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%99%9A%E6%8B%9F%E5%86%85%E5%AD%98%E4%B8%8E%E7%89%A9%E7%90%86%E5%86%85%E5%AD%98/https://blog.zoloy.top/posts/%E8%99%9A%E6%8B%9F%E5%86%85%E5%AD%98%E4%B8%8E%E7%89%A9%E7%90%86%E5%86%85%E5%AD%98/虚拟内存通过 MMU 加页表加 TLB 加缺页中断让每个进程拥有独占内存的幻觉，同时实现隔离与高效利用。Sun, 29 Jun 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E7%BA%BF%E7%A8%8B%E9%97%B4%E9%80%9A%E8%AE%AF%E6%96%B9%E5%BC%8F/https://blog.zoloy.top/posts/%E7%BA%BF%E7%A8%8B%E9%97%B4%E9%80%9A%E8%AE%AF%E6%96%B9%E5%BC%8F/线程间通讯的本质挑战不是传递数据而是安全地访问共享内存，五种同步机制各有适用临界区长度。Thu, 26 Jun 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E7%94%A8%E6%88%B7%E6%80%81%E5%92%8C%E5%86%85%E6%A0%B8%E6%80%81/https://blog.zoloy.top/posts/%E7%94%A8%E6%88%B7%E6%80%81%E5%92%8C%E5%86%85%E6%A0%B8%E6%80%81/CPU 通过 Ring 0/3 硬件特权级实现用户态与内核态隔离，系统调用是跨越特权级的唯一合法桥梁。Tue, 24 Jun 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E6%AD%BB%E9%94%81%E7%9A%84%E5%9B%9B%E4%B8%AA%E6%9D%A1%E4%BB%B6%E4%B8%8E%E9%93%B6%E8%A1%8C%E5%AE%B6%E7%AE%97%E6%B3%95/https://blog.zoloy.top/posts/%E6%AD%BB%E9%94%81%E7%9A%84%E5%9B%9B%E4%B8%AA%E6%9D%A1%E4%BB%B6%E4%B8%8E%E9%93%B6%E8%A1%8C%E5%AE%B6%E7%AE%97%E6%B3%95/死锁是四个条件同时满足的必然结果，破坏任一条件即可免疫，资源有序分配是最常用的工程实践。Sat, 21 Jun 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E6%93%8D%E4%BD%9C%E7%B3%BB%E7%BB%9F%E5%86%85%E5%AD%98%E4%B8%8D%E8%B6%B3%E5%A4%84%E7%90%86/https://blog.zoloy.top/posts/%E6%93%8D%E4%BD%9C%E7%B3%BB%E7%BB%9F%E5%86%85%E5%AD%98%E4%B8%8D%E8%B6%B3%E5%A4%84%E7%90%86/从缺页中断到 kswapd 后台回收再到 OOM Killer 的完整内存回收递进链条，揭示了 Linux 内存管理的层层兜底机制。Thu, 19 Jun 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%A0%86%E5%92%8C%E6%A0%88%E7%9A%84%E5%8C%BA%E5%88%AB/https://blog.zoloy.top/posts/%E5%A0%86%E5%92%8C%E6%A0%88%E7%9A%84%E5%8C%BA%E5%88%AB/从内存布局到分配原理全面对比堆与栈：栈由编译器自动管理高效有序，堆由程序员手动管理灵活但易碎片。Mon, 16 Jun 2025 09:00:00 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GMThttps://blog.zoloy.top/posts/brk%E4%B8%8Emmap%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/brk%E4%B8%8Emmap%E8%AF%A6%E8%A7%A3/malloc 底层通过 brk 移动堆顶分配小块内存，通过 mmap 创建匿名映射分配大块内存，深刻理解双引擎对内存效率的影响。Wed, 04 Jun 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%B4%A3%E4%BB%BB%E9%93%BE%E6%A8%A1%E5%BC%8F-servlet-filterchain/https://blog.zoloy.top/posts/%E8%B4%A3%E4%BB%BB%E9%93%BE%E6%A8%A1%E5%BC%8F-servlet-filterchain/Tomcat FilterChain 用迭代加 pos 索引替代递归避免栈溢出，Spring Interceptor 逆序补偿保证执行对称性。Sun, 01 Jun 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%A7%82%E5%AF%9F%E8%80%85%E6%A8%A1%E5%BC%8F/https://blog.zoloy.top/posts/%E8%A7%82%E5%AF%9F%E8%80%85%E6%A8%A1%E5%BC%8F/观察者模式将硬编码调用链解耦为发布订阅网络，配合事务监听器和异步执行构建灵活的事件驱动架构。Fri, 30 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%A3%85%E9%A5%B0%E5%99%A8%E6%A8%A1%E5%BC%8F-javaio/https://blog.zoloy.top/posts/%E8%A3%85%E9%A5%B0%E5%99%A8%E6%A8%A1%E5%BC%8F-javaio/装饰器模式用组合替代继承实现功能叠加，Java IO 的洋葱模型用 N 加 M 个类覆盖 N 乘 M 种功能组合。Tue, 27 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E7%AD%96%E7%95%A5%E6%A8%A1%E5%BC%8F-map%E6%B3%A8%E5%85%A5%E6%B6%88%E9%99%A4if-else/https://blog.zoloy.top/posts/%E7%AD%96%E7%95%A5%E6%A8%A1%E5%BC%8F-map%E6%B3%A8%E5%85%A5%E6%B6%88%E9%99%A4if-else/Spring 通过@Autowired Map 注入收集所有策略实现，完全消除 if-else 分支，新增策略只需加 Component 类。Sun, 25 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E6%A8%A1%E6%9D%BF%E6%96%B9%E6%B3%95%E6%A8%A1%E5%BC%8F-jdbctemplate/https://blog.zoloy.top/posts/%E6%A8%A1%E6%9D%BF%E6%96%B9%E6%B3%95%E6%A8%A1%E5%BC%8F-jdbctemplate/父类固定流程骨架，子类实现可变步骤，JdbcTemplate 将连接管理与异常翻译抽离为模板，回调只需写 SQL。Fri, 23 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%BB%BA%E9%80%A0%E8%80%85%E6%A8%A1%E5%BC%8F/https://blog.zoloy.top/posts/%E5%BB%BA%E9%80%A0%E8%80%85%E6%A8%A1%E5%BC%8F/建造者模式用链式调用替代多参构造器，将必填参数通过构造函数强制传入，可选参数通过 setter 设置。Tue, 20 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%8E%9F%E5%9E%8B%E6%A8%A1%E5%BC%8F/https://blog.zoloy.top/posts/%E5%8E%9F%E5%9E%8B%E6%A8%A1%E5%BC%8F/原型模式通过克隆已有对象避免昂贵的构造过程，重点理解 Java 中浅拷贝与深拷贝的本质区别及 Cloneable 的实现细节。Sun, 18 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%8D%95%E4%BE%8B%E6%A8%A1%E5%BC%8F%E7%9A%845%E7%A7%8D%E5%86%99%E6%B3%95/https://blog.zoloy.top/posts/%E5%8D%95%E4%BE%8B%E6%A8%A1%E5%BC%8F%E7%9A%845%E7%A7%8D%E5%86%99%E6%B3%95/从饿汉到枚举的五种单例写法演进：饿汉安全、DCL 巧妙、静态内部类优雅、枚举防反射，每种写法有其适用场景。Thu, 15 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%B7%A5%E5%8E%82%E6%A8%A1%E5%BC%8F-spring-factorybean/https://blog.zoloy.top/posts/%E5%B7%A5%E5%8E%82%E6%A8%A1%E5%BC%8F-spring-factorybean/FactoryBean 将复杂 Bean 的创建逻辑封装到独立类中，getBean 返回产品而非工厂实例。Tue, 13 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/spring%E4%BA%8B%E5%8A%A1%E4%BC%A0%E6%92%AD%E4%B8%8E%E5%A4%B1%E6%95%88/https://blog.zoloy.top/posts/spring%E4%BA%8B%E5%8A%A1%E4%BC%A0%E6%92%AD%E4%B8%8E%E5%A4%B1%E6%95%88/梳理 Spring 事务七种传播行为与@Transactional 失效的六种场景——同类 this 调用绕过代理、非 public 方法、异常被吞、未配 rollbackFor 等，根因归结为调用未经过 AOP 代理。Sat, 10 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/springboot%E8%87%AA%E5%8A%A8%E8%A3%85%E9%85%8D%E5%8E%9F%E7%90%86/https://blog.zoloy.top/posts/springboot%E8%87%AA%E5%8A%A8%E8%A3%85%E9%85%8D%E5%8E%9F%E7%90%86/拆解@SpringBootApplication 背后的自动装配全流程——@EnableAutoConfiguration 触发候选类加载，@Conditional 条件筛选约 150 个配置类，实现引入依赖即可用的约定优于配置。Thu, 08 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/spring-%E5%BE%AA%E7%8E%AF%E4%BE%9D%E8%B5%96-%E4%B8%89%E7%BA%A7%E7%BC%93%E5%AD%98/https://blog.zoloy.top/posts/spring-%E5%BE%AA%E7%8E%AF%E4%BE%9D%E8%B5%96-%E4%B8%89%E7%BA%A7%E7%BC%93%E5%AD%98/逐层剖析 Spring 三级缓存解决循环依赖的精妙设计——一级存成品、二级暴露半成品打破循环、三级用 ObjectFactory 延迟生成代理保证 AOP 代理唯一性，以及构造器注入为何无解。Mon, 05 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/spring-ioc%E5%AE%B9%E5%99%A8-bean%E7%94%9F%E5%91%BD%E5%91%A8%E6%9C%9F/https://blog.zoloy.top/posts/spring-ioc%E5%AE%B9%E5%99%A8-bean%E7%94%9F%E5%91%BD%E5%91%A8%E6%9C%9F/从 BeanDefinition 到 Bean 实例的完整旅程——解析配置生成元数据、BFPP 修改配方、反射实例化、依赖注入、BPP 链处理与 AOP 代理生成，理清 BFPP 与 BPP 的阶段性分离设计。Sat, 03 May 2025 09:00:00 GMThttps://blog.zoloy.top/posts/spring-aop-jdk%E5%8A%A8%E6%80%81%E4%BB%A3%E7%90%86-vs-cglib/https://blog.zoloy.top/posts/spring-aop-jdk%E5%8A%A8%E6%80%81%E4%BB%A3%E7%90%86-vs-cglib/对比 JDK 动态代理与 CGLIB 的底层机制——JDK 依赖接口+反射调用，CGLIB 通过子类+FastClass 索引实现非反射调用，Spring Boot 2.x 为何强制默认 CGLIB。Wed, 30 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq%E5%BB%B6%E6%97%B6%E6%B6%88%E6%81%AF%E7%9A%84%E5%BA%95%E5%B1%82%E5%AE%9E%E7%8E%B0/https://blog.zoloy.top/posts/rocketmq%E5%BB%B6%E6%97%B6%E6%B6%88%E6%81%AF%E7%9A%84%E5%BA%95%E5%B1%82%E5%AE%9E%E7%8E%B0/揭开 RocketMQ 延时消息底层实现——Broker 拦截后存入 SCHEDULE_TOPIC_XXXX 内部 Topic，ScheduleMessageService 每秒轮询到期消息恢复投递，引起约 1 秒精度偏差。Mon, 28 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E9%A1%BA%E5%BA%8F%E6%B6%88%E8%B4%B9/https://blog.zoloy.top/posts/rocketmq-%E9%A1%BA%E5%BA%8F%E6%B6%88%E8%B4%B9/梳理 RocketMQ 顺序消费的三环接力——生产者取模路由到同一队列、Broker FIFO 存储、Consumer 分布式锁+单线程绑定，以及 SUSPEND_CURRENT_QUEUE_A_MOMENT 的可靠性设计。Fri, 25 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E9%A2%86%E5%9F%9F%E6%A8%A1%E5%9E%8B/https://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E9%A2%86%E5%9F%9F%E6%A8%A1%E5%9E%8B/逐层拆解 RocketMQ 五层领域模型——Topic 命名空间、Tag 二级分类、MessageQueue 物理队列、ConsumerGroup 逻辑分组与 Offset 64 位指针，纠正七个常见误解。Wed, 23 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E8%BF%87%E6%BB%A4/https://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E8%BF%87%E6%BB%A4/解析 RocketMQ 三级过滤漏斗——Tag 哈希在 ConsumeQueue 层 O(1)过滤不读磁盘，SQL92 表达式需读 CommitLog 但有灵活性，消费端二次过滤作为最后防线防哈希冲突。Sun, 20 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E7%A7%AF%E5%8E%8B%E5%A4%84%E7%90%86/https://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E7%A7%AF%E5%8E%8B%E5%A4%84%E7%90%86/消息积压从发现到消除的全链路方案——监控指标与告警阈值、生产者流控止血、消费端扩缩容与批量优化、DLQ 兜底毒消息，以及基于 Lag 的 K8s 自动弹性伸缩。Fri, 18 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E5%B9%82%E7%AD%89%E6%80%A7/https://blog.zoloy.top/posts/rocketmq-%E6%B6%88%E6%81%AF%E5%B9%82%E7%AD%89%E6%80%A7/剖析 RocketMQ 消息重复的三种来源与为什么 MessageId 不可靠，对比四种幂等方案——数据库唯一索引、Redis SETNX、业务状态机与 Broker 端去重，强调消费端是最后防线。Wed, 16 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E6%AD%BB%E4%BF%A1%E9%98%9F%E5%88%97dlq/https://blog.zoloy.top/posts/rocketmq-%E6%AD%BB%E4%BF%A1%E9%98%9F%E5%88%97dlq/解析 RocketMQ 死信队列作为 16 次重试后的最终防线——延迟递增重试策略防止资源浪费，DLQ 隔离毒消息保障正常流，人工介入修复后手动回放。Sun, 13 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E6%9E%B6%E6%9E%84%E8%AE%BE%E8%AE%A1-commitlog/https://blog.zoloy.top/posts/rocketmq-%E6%9E%B6%E6%9E%84%E8%AE%BE%E8%AE%A1-commitlog/剖析 RocketMQ 三个核心架构取舍——CommitLog 单文件顺序追加实现极致写性能，ConsumeQueue 固定 20 字节二级索引换一次随机读，NameServer 无主设计换零运维。Fri, 11 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E5%BB%B6%E6%97%B6%E6%B6%88%E6%81%AF%E5%8E%9F%E7%90%86/https://blog.zoloy.top/posts/rocketmq-%E5%BB%B6%E6%97%B6%E6%B6%88%E6%81%AF%E5%8E%9F%E7%90%86/拆解 RocketMQ 18 级延时消息的完整生命周期——从写入 SCHEDULE_TOPIC_XXXX 按 delayLevel 分 Queue，到 ScheduleMessageService 定时扫描投递，展示时间分桶替代独立计时的架构取舍。Tue, 08 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E5%88%B7%E7%9B%98%E6%9C%BA%E5%88%B6/https://blog.zoloy.top/posts/rocketmq-%E5%88%B7%E7%9B%98%E6%9C%BA%E5%88%B6/详解 RocketMQ 同步刷盘与异步刷盘的区别，深入 mmap 内存映射文件与顺序写磁盘如何实现高吞吐，以及 GroupCommit 组提交优化同步刷盘性能。Sun, 06 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-%E4%BA%8B%E5%8A%A1%E6%B6%88%E6%81%AF-half-message/https://blog.zoloy.top/posts/rocketmq-%E4%BA%8B%E5%8A%A1%E6%B6%88%E6%81%AF-half-message/拆解 RocketMQ 事务消息的 Half Message 二阶段提交机制——消息先写 RMQ_SYS_TRANS_HALF_TOPIC 不可见，本地事务执行后 Commit/Rollback，回查机制兜底网络丢包。Thu, 03 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-vs-kafka%E5%AF%B9%E6%AF%94/https://blog.zoloy.top/posts/rocketmq-vs-kafka%E5%AF%B9%E6%AF%94/全维度对比 RocketMQ 与 Kafka 的性能、存储模型、功能矩阵与生态差异——为什么 Kafka 怕多 Topic，以及 sendfile 与 mmap 零拷贝实现的不同取舍。Tue, 01 Apr 2025 09:00:00 GMThttps://blog.zoloy.top/posts/rocketmq-consumequeue%E7%B4%A2%E5%BC%95/https://blog.zoloy.top/posts/rocketmq-consumequeue%E7%B4%A2%E5%BC%95/深入解析 ConsumeQueue 固定 20 字节索引条目的设计精妙——8 字节 CommitLog 偏移+4 字节大小+8 字节 Tag 哈希，实现 O(1)消息定位的二级索引体系。Sat, 29 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E7%BC%93%E5%AD%98%E8%AE%BE%E8%AE%A1-%E7%A9%BF%E9%80%8F-%E5%87%BB%E7%A9%BF-%E9%9B%AA%E5%B4%A9/https://blog.zoloy.top/posts/%E7%BC%93%E5%AD%98%E8%AE%BE%E8%AE%A1-%E7%A9%BF%E9%80%8F-%E5%87%BB%E7%A9%BF-%E9%9B%AA%E5%B4%A9/缓存穿透用布隆过滤器拦截非法 key，击穿用互斥锁保证单线程回源，雪崩用 TTL 随机化分散过期时间。Thu, 27 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%B8%83%E9%9A%86%E8%BF%87%E6%BB%A4%E5%99%A8%E7%9A%84%E5%8F%8C%E9%87%8D%E5%93%88%E5%B8%8C%E6%8A%80%E5%B7%A7/https://blog.zoloy.top/posts/%E5%B8%83%E9%9A%86%E8%BF%87%E6%BB%A4%E5%99%A8%E7%9A%84%E5%8F%8C%E9%87%8D%E5%93%88%E5%B8%8C%E6%8A%80%E5%B7%A7/通过一次 MurmurHash3 调用的高低 32 位做线性组合，模拟 k 个独立哈希函数的效果。Mon, 24 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%B8%83%E9%9A%86%E8%BF%87%E6%BB%A4%E5%99%A8-%E5%B8%83%E8%B0%B7%E9%B8%9F%E8%BF%87%E6%BB%A4%E5%99%A8/https://blog.zoloy.top/posts/%E5%B8%83%E9%9A%86%E8%BF%87%E6%BB%A4%E5%99%A8-%E5%B8%83%E8%B0%B7%E9%B8%9F%E8%BF%87%E6%BB%A4%E5%99%A8/布隆过滤器位数组共享导致不可删除，布谷鸟过滤器用 XOR 可逆指纹实现双向定位与删除。Sat, 22 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/ziplist%E8%BF%9E%E9%94%81%E6%9B%B4%E6%96%B0%E4%B8%8Elistpack/https://blog.zoloy.top/posts/ziplist%E8%BF%9E%E9%94%81%E6%9B%B4%E6%96%B0%E4%B8%8Elistpack/ZipList 的连锁更新问题根因在于变长编码依赖前驱节点，listpack 通过自描述编码彻底根除这一设计缺陷。Wed, 19 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis%E6%B8%90%E8%BF%9B%E5%BC%8Frehash/https://blog.zoloy.top/posts/redis%E6%B8%90%E8%BF%9B%E5%BC%8Frehash/揭示 Redis 如何通过 ht[0]/ht[1]双表+rehashidx 游标，将 O(n)全量迁移拆为 n 次 O(1)微步，在每次读写命令中顺带推进，配合 serverCron 毫秒级时间预算兜底。Mon, 17 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redisson%E5%88%86%E5%B8%83%E5%BC%8F%E9%94%81%E7%9A%84lua%E8%84%9A%E6%9C%AC%E5%AE%9E%E7%8E%B0/https://blog.zoloy.top/posts/redisson%E5%88%86%E5%B8%83%E5%BC%8F%E9%94%81%E7%9A%84lua%E8%84%9A%E6%9C%AC%E5%AE%9E%E7%8E%B0/剖析 Redisson 如何用一段 Lua 脚本解决手写 SET NX EX 的三个经典坑——锁超时误删、不可重入与释放原子性，以及 WatchDog 自动续期机制。Fri, 14 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-%E7%BC%93%E5%AD%98%E6%9B%B4%E6%96%B0%E7%AD%96%E7%95%A5%E4%B8%89%E5%A4%A7%E6%A8%A1%E5%BC%8F/https://blog.zoloy.top/posts/redis-%E7%BC%93%E5%AD%98%E6%9B%B4%E6%96%B0%E7%AD%96%E7%95%A5%E4%B8%89%E5%A4%A7%E6%A8%A1%E5%BC%8F/对比 Cache Aside、Read/Write Through 与 Write Back 三种缓存更新模式的核心原理、一致性保证和适用场景，给出生产环境的选型决策树。Wed, 12 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-%E6%B7%98%E6%B1%B0%E7%AD%96%E7%95%A5%E8%AF%A6%E8%A7%A3lru-lfu/https://blog.zoloy.top/posts/redis-%E6%B7%98%E6%B1%B0%E7%AD%96%E7%95%A5%E8%AF%A6%E8%A7%A3lru-lfu/对比 Redis 八种内存淘汰策略，重点剖析近似 LRU 随机采样算法与 LFU 对数计数器+时间衰减的精妙设计，以及三者关键参数调优指南。Mon, 10 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-%E5%A4%A7key%E5%A4%84%E7%90%86/https://blog.zoloy.top/posts/redis-%E5%A4%A7key%E5%A4%84%E7%90%86/完整指南——从大 key 的定义、排查工具到安全删除，涵盖 UNLINK 异步删除与各数据类型分批删除的最佳实践。Fri, 07 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-%E5%93%A8%E5%85%B5%E9%80%89%E4%B8%BB/https://blog.zoloy.top/posts/redis-%E5%93%A8%E5%85%B5%E9%80%89%E4%B8%BB/详解 Redis Sentinel 故障转移全流程，包括主观/客观下线判定、Raft 风格 Leader 选举与三轮打分选主机制，以及 min-slaves-to-write 脑裂防护。Wed, 05 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-quicklist%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/redis-quicklist%E8%AF%A6%E8%A7%A3/解析 quicklist 双向链表+ziplist/listpack 混合结构，如何兼顾链表快速头尾操作与压缩列表低指针开销，并将连锁更新控制在一个节点范围内。Sun, 02 Mar 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-jemalloc%E5%86%85%E5%AD%98%E5%88%86%E9%85%8D%E5%99%A8/https://blog.zoloy.top/posts/redis-jemalloc%E5%86%85%E5%AD%98%E5%88%86%E9%85%8D%E5%99%A8/详解 Redis 默认内存分配器 jemalloc 的四层架构——tcache 线程缓存、细粒度 size class、红黑树 extent 管理与延迟回收如何实现低碎片率。Fri, 28 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-stream%E6%B6%88%E6%81%AF%E9%98%9F%E5%88%97/https://blog.zoloy.top/posts/redis-stream%E6%B6%88%E6%81%AF%E9%98%9F%E5%88%97/介绍 Redis Stream 消息队列——支持消费者组、ACK 确认与消息持久化，填补 List 和 Pub/Sub 在轻量级可靠消息场景的空白。Tue, 25 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-sds%E4%B8%8Eembstr%E7%9A%8444%E5%AD%97%E8%8A%82%E9%98%88%E5%80%BC/https://blog.zoloy.top/posts/redis-sds%E4%B8%8Eembstr%E7%9A%8444%E5%AD%97%E8%8A%82%E9%98%88%E5%80%BC/从 SDS 五种头类型到 RedisObject，完整推导 embstr 的 44 字节阈值——如何精确填满 jemalloc 64 字节 bucket，实现一次 malloc 零指针开销。Sun, 23 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-rdb-aof%E6%8C%81%E4%B9%85%E5%8C%96/https://blog.zoloy.top/posts/redis-rdb-aof%E6%8C%81%E4%B9%85%E5%8C%96/对比 Redis 三种持久化机制——RDB 快照、AOF 写后日志与混合持久化，解析 bgrewriteaof 子进程如何通过双缓冲区不丢数据。Thu, 20 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-geo%E5%9C%B0%E7%90%86%E4%BD%8D%E7%BD%AE/https://blog.zoloy.top/posts/redis-geo%E5%9C%B0%E7%90%86%E4%BD%8D%E7%BD%AE/揭示 Redis GEO 基于 Sorted Set 的实现原理——GeoHash 将二维经纬度编码为 52 位整数，利用 ZRANGEBYSCORE 实现高效地理位置范围查询。Tue, 18 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/redis-cluster-%E6%97%A0%E6%84%9F%E6%89%A9%E5%AE%B9/https://blog.zoloy.top/posts/redis-cluster-%E6%97%A0%E6%84%9F%E6%89%A9%E5%AE%B9/剖析 Redis Cluster 在线扩容核心机制——slot 粒度的在线迁移与 MOVED/ASK 重定向，实现业务无感知的集群水平扩展。Sat, 15 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql%E8%87%AA%E9%80%82%E5%BA%94%E5%93%88%E5%B8%8C%E7%B4%A2%E5%BC%95ahi/https://blog.zoloy.top/posts/mysql%E8%87%AA%E9%80%82%E5%BA%94%E5%93%88%E5%B8%8C%E7%B4%A2%E5%BC%95ahi/AHI 在 BufferPool 中自动构建哈希表加速高频等值查询，键映射到叶子页而非行，范围查询不触发，高并发写入场景建议关闭Thu, 13 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql%E7%B4%A2%E5%BC%95%E4%B8%8B%E6%8E%A8icp/https://blog.zoloy.top/posts/mysql%E7%B4%A2%E5%BC%95%E4%B8%8B%E6%8E%A8icp/ICP 将 WHERE 条件中索引列判断下推到存储引擎层减少回表，覆盖索引自动跳过 ICP，与 MRR 配合先过滤再排序批量回表Mon, 10 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql%E5%B9%B6%E8%A1%8C%E5%9B%9E%E6%94%BEmts/https://blog.zoloy.top/posts/mysql%E5%B9%B6%E8%A1%8C%E5%9B%9E%E6%94%BEmts/MTS 多线程并行回放解决主从延迟，LOGICAL_CLOCK 基于事务提交时间戳判依赖，单库场景优于仅按 Schema 并行的 DATABASE 模式Sat, 08 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql%E5%AD%98%E5%82%A8%E5%BC%95%E6%93%8E%E4%BA%94%E5%B1%82%E6%A8%A1%E5%9E%8B/https://blog.zoloy.top/posts/mysql%E5%AD%98%E5%82%A8%E5%BC%95%E6%93%8E%E4%BA%94%E5%B1%82%E6%A8%A1%E5%9E%8B/InnoDB 五层存储架构表空间段区页行，页为 16KB 最小 IO 单元含 Page Directory 二分查找，区为 1MB 连续空间分配的基本单位Wed, 05 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql%E5%8D%8A%E5%90%8C%E6%AD%A5%E5%A4%8D%E5%88%B6/https://blog.zoloy.top/posts/mysql%E5%8D%8A%E5%90%8C%E6%AD%A5%E5%A4%8D%E5%88%B6/半同步复制 after_sync 模式主库等至少一个从库 ACK 写入 relay log 后才返回成功，超时降级异步防阻塞，主库宕机不丢已确认数据Mon, 03 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql%E4%B8%A4%E9%98%B6%E6%AE%B5%E6%8F%90%E4%BA%A4%E4%B8%8E%E5%B4%A9%E6%BA%83%E6%81%A2%E5%A4%8D/https://blog.zoloy.top/posts/mysql%E4%B8%A4%E9%98%B6%E6%AE%B5%E6%8F%90%E4%BA%A4%E4%B8%8E%E5%B4%A9%E6%BA%83%E6%81%A2%E5%A4%8D/MySQL 内部 2PC 协调 redo 与 binlog 双日志一致性，binlog 完整则提交否则回滚，XID 贯穿两端，组提交多事务合并一次 fsyncSat, 01 Feb 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-%E8%81%94%E5%90%88%E7%B4%A2%E5%BC%95-%E6%9C%80%E5%B7%A6%E5%89%8D%E7%BC%80/https://blog.zoloy.top/posts/mysql-%E8%81%94%E5%90%88%E7%B4%A2%E5%BC%95-%E6%9C%80%E5%B7%A6%E5%89%8D%E7%BC%80/联合索引最左前缀是 B+树多字段排序的物理结果非人为限制，范围查询后列失效因跨值后不再全局有序，ICP 可减少回表Wed, 29 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-%E6%B7%B1%E5%88%86%E9%A1%B5%E4%BC%98%E5%8C%96/https://blog.zoloy.top/posts/mysql-%E6%B7%B1%E5%88%86%E9%A1%B5%E4%BC%98%E5%8C%96/深分页慢因 offset 大导致大量回表 IO，延迟关联让扫描在索引层完成免回表，游标分页用索引定位替代 offset 实现恒定性能Mon, 27 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-%E4%B8%B4%E9%94%AE%E9%94%81%E9%80%80%E5%8C%96/https://blog.zoloy.top/posts/mysql-%E4%B8%B4%E9%94%AE%E9%94%81%E9%80%80%E5%8C%96/InnoDB 行锁三件套：临键锁等值查询加唯一索引时触发退化，记录存在变记录锁释放间隙，不存在变间隙锁防幻插Fri, 24 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-join%E4%BC%98%E5%8C%96-nlj-bka/https://blog.zoloy.top/posts/mysql-join%E4%BC%98%E5%8C%96-nlj-bka/JOIN 四种算法从 Simple NLJ 到 BKA 演进，被驱动表 JOIN 列加索引是小表驱动大表前提，六种常见索引失效场景需规避Wed, 22 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-change-buffer/https://blog.zoloy.top/posts/mysql-change-buffer/Change Buffer 缓存非唯一二级索引变更将随机 IO 转顺序写，仅限于非唯一索引因唯一性检查必须读索引页，写后立即查询是反模式Sun, 19 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-undo-log%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/mysql-undo-log%E8%AF%A6%E8%A7%A3/Undo Log 双重使命：事务回滚与 MVCC 版本链构建，长事务导致 undo 膨胀根因是活跃 ReadView 阻止 purge 线程清理旧版本Fri, 17 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-mvcc-readview/https://blog.zoloy.top/posts/mysql-mvcc-readview/ReadView 四字段可见性判断算法：遍历 undo 版本链比较 trx_id 与 m_ids 边界，RC 每次重建 ReadView，RR 复用至事务结束Tue, 14 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-mha%E6%95%85%E9%9A%9C%E5%88%87%E6%8D%A2%E4%B8%8E%E8%84%91%E8%A3%82%E9%98%B2%E6%8A%A4/https://blog.zoloy.top/posts/mysql-mha%E6%95%85%E9%9A%9C%E5%88%87%E6%8D%A2%E4%B8%8E%E8%84%91%E8%A3%82%E9%98%B2%E6%8A%A4/MHA 故障切换五阶段时间线、STONITH 物理断电防脑裂、VIP 漂移三层防护，secondary_check_script 多路径验证防误切Sun, 12 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-gtid%E5%A4%8D%E5%88%B6/https://blog.zoloy.top/posts/mysql-gtid%E5%A4%8D%E5%88%B6/GTID 用 UUID 加事务序号作逻辑标识替代物理偏移，从库自动求差集续接，主从切换无需手动指定 binlog 文件和位置Thu, 09 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-explain-%E6%89%A7%E8%A1%8C%E8%AE%A1%E5%88%92/https://blog.zoloy.top/posts/mysql-explain-%E6%89%A7%E8%A1%8C%E8%AE%A1%E5%88%92/EXPLAIN 字段解读：type 访问类型从 const 到 ALL 逐级变差，key 看实际使用的索引，Extra 中 Using filesort 需优先优化Tue, 07 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/mysql-bufferpool-doublewrite/https://blog.zoloy.top/posts/mysql-bufferpool-doublewrite/InnoDB 分区 LRU 防全表扫描污染 young 区热数据，Double Write 先顺序写 dblwr 备份再离散写数据文件防止页断裂Sat, 04 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/volatile-%E5%86%85%E5%AD%98%E5%B1%8F%E9%9A%9C/https://blog.zoloy.top/posts/volatile-%E5%86%85%E5%AD%98%E5%B1%8F%E9%9A%9C/volatile 通过内存屏障保证可见性与有序性，禁止指令重排序是 DCL 安全实现的关键，深入理解 StoreLoad 等四大屏障。Thu, 02 Jan 2025 09:00:00 GMThttps://blog.zoloy.top/posts/unsafe%E7%B1%BB-juc%E5%9F%BA%E7%9F%B3/https://blog.zoloy.top/posts/unsafe%E7%B1%BB-juc%E5%9F%BA%E7%9F%B3/Unsafe 提供 CAS 原子操作、内存屏障和直接内存访问三类底层能力，是 JUC 所有无锁并发结构的基石。Mon, 30 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/transmittablethreadlocal/https://blog.zoloy.top/posts/transmittablethreadlocal/阿里巴巴 TTL 通过装饰任务实现线程池场景下的上下文无损传递，解决 ThreadLocal 和 InheritableThreadLocal 的线程复用污染问题。Sat, 28 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/threadlocal%E5%86%85%E5%AD%98%E6%B3%84%E6%BC%8F/https://blog.zoloy.top/posts/threadlocal%E5%86%85%E5%AD%98%E6%B3%84%E6%BC%8F/ThreadLocal 的弱引用 key 被 GC 回收后 value 仍无法释放，详解内存泄漏完整链路及 get/set/remove 的过期清理机制。Thu, 26 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/scheduledthreadpoolexecutor/https://blog.zoloy.top/posts/scheduledthreadpoolexecutor/分析 Timer 单线程设计的三个致命缺陷，对比 ScheduledThreadPoolExecutor 基于 DelayedWorkQueue 最小堆的多线程调度架构，以及 fixed-rate 与 fixed-delay 两种模式的核心区别。Mon, 23 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/mdc%E7%9A%84threadlocal%E6%B3%84%E6%BC%8F%E4%B8%8Escopedvalue/https://blog.zoloy.top/posts/mdc%E7%9A%84threadlocal%E6%B3%84%E6%BC%8F%E4%B8%8Escopedvalue/MDC 底层双 ThreadLocal 缓存设计原理，虚拟线程下 ThreadLocal 强引用 Value 导致泄漏，ScopedValue 作用域绑定自动释放Sat, 21 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/longadder-atomiclong-contended/https://blog.zoloy.top/posts/longadder-atomiclong-contended/LongAdder 通过 Cell 数组分槽降低 CAS 竞争，@Contended 消除伪共享保证分槽独立性，以 sum()最终一致性换高并发写入性能Wed, 18 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/java%E7%BA%BF%E7%A8%8B%E6%B1%A0-execute%E4%BA%8C%E6%AC%A1%E6%A3%80%E6%9F%A5/https://blog.zoloy.top/posts/java%E7%BA%BF%E7%A8%8B%E6%B1%A0-execute%E4%BA%8C%E6%AC%A1%E6%A3%80%E6%9F%A5/线程池 execute()入队后二次检查：防无线程消费队列与 shutdown 时任务悬空，保证竞态场景下任务语义一致Mon, 16 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/forkjoinpool%E5%88%86%E6%B2%BB%E5%B9%B6%E8%A1%8C/https://blog.zoloy.top/posts/forkjoinpool%E5%88%86%E6%B2%BB%E5%B9%B6%E8%A1%8C/ForkJoinPool 用不对称双端队列实现工作窃取：自身 LIFO 取最新 Fork 保留缓存局部性，偷取者 FIFO 从栈底取大粒度任务实现负载均衡。Fri, 13 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/countdownlatch-cyclicbarrier-semaphore/https://blog.zoloy.top/posts/countdownlatch-cyclicbarrier-semaphore/CountDownLatch 一次性倒计数适合主等子，CyclicBarrier 可重置栅栏适合多阶段同步，Semaphore 控制并发数适合限流与连接池。Wed, 11 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/completablefuture%E5%BC%82%E6%AD%A5%E7%BC%96%E7%A8%8B/https://blog.zoloy.top/posts/completablefuture%E5%BC%82%E6%AD%A5%E7%BC%96%E7%A8%8B/CompletableFuture 用 thenApply/thenCombine 链式编排异步任务，但默认共用 ForkJoinPool.commonPool，IO 密集任务须自定义线程池避免阻塞共享资源。Sun, 08 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/aqs-%E9%98%9F%E5%88%97%E5%90%8C%E6%AD%A5%E5%99%A8/https://blog.zoloy.top/posts/aqs-%E9%98%9F%E5%88%97%E5%90%8C%E6%AD%A5%E5%99%A8/AQS 将阻塞、排队、唤醒抽离为抽象基类，子类只需定义 tryAcquire/tryRelease 语义，实现锁与同步器的统一底座。Fri, 06 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/%E7%BA%BF%E4%B8%8A%E6%8E%92%E6%9F%A5-arthas-%E5%B7%A5%E5%85%B7%E9%93%BE/https://blog.zoloy.top/posts/%E7%BA%BF%E4%B8%8A%E6%8E%92%E6%9F%A5-arthas-%E5%B7%A5%E5%85%B7%E9%93%BE/从 top 定位 CPU 到 Arthas trace 精准定位方法耗时，构建 Java 线上排查的五场景完整工具链。Tue, 03 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/synchronized%E9%94%81%E5%8D%87%E7%BA%A7%E6%9C%BA%E5%88%B6/https://blog.zoloy.top/posts/synchronized%E9%94%81%E5%8D%87%E7%BA%A7%E6%9C%BA%E5%88%B6/synchronized 根据竞争程度自动升级：无锁→偏向锁→轻量级锁→重量级锁，通过 Mark Word 编码锁状态实现无竞争零开销。Sun, 01 Dec 2024 09:00:00 GMThttps://blog.zoloy.top/posts/happens-before%E8%A7%84%E5%88%99%E8%AF%A6%E8%A7%A3/https://blog.zoloy.top/posts/happens-before%E8%A7%84%E5%88%99%E8%AF%A6%E8%A7%A3/JMM 的 8 条 happens-before 规则定义了多线程下变量修改的可见性保证，是理解 volatile、锁、并发工具的前提。Thu, 28 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/oom%E7%B1%BB%E5%9E%8B%E5%85%A8%E6%99%AF%E6%8E%92%E6%9F%A5/https://blog.zoloy.top/posts/oom%E7%B1%BB%E5%9E%8B%E5%85%A8%E6%99%AF%E6%8E%92%E6%9F%A5/四种 OOM 全景排查：堆 OOM 用 MAT 支配树找泄漏源、元空间查 ClassLoader、栈溢出看递归、直接内存手动 cleaner 释放Tue, 26 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/jvm%E8%BF%90%E8%A1%8C%E6%97%B6%E6%95%B0%E6%8D%AE%E5%8C%BA/https://blog.zoloy.top/posts/jvm%E8%BF%90%E8%A1%8C%E6%97%B6%E6%95%B0%E6%8D%AE%E5%8C%BA/JVM 运行时区分为线程共享的堆与元空间、线程私有的虚拟机栈与 PC 寄存器，不同 OOM 类型精确对应各自所属内存区域。Sat, 23 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/jvm%E4%B8%89%E8%89%B2%E6%A0%87%E8%AE%B0%E4%B8%8E%E6%BC%8F%E6%A0%87/https://blog.zoloy.top/posts/jvm%E4%B8%89%E8%89%B2%E6%A0%87%E8%AE%B0%E4%B8%8E%E6%BC%8F%E6%A0%87/三色标记中漏标的充要条件是黑色对象新增白引用且灰色到白引用被删，CMS 用写后屏障增量更新，G1 用写前屏障 SATB 保留快照。Thu, 21 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/jvm-%E6%8C%87%E9%92%88%E5%8E%8B%E7%BC%A9/https://blog.zoloy.top/posts/jvm-%E6%8C%87%E9%92%88%E5%8E%8B%E7%BC%A9/利用对象 8 字节对齐低 3 位恒零，将 64 位地址右移 3 位压缩为 32 位存储，解码时左移恢复，4 字节指针寻址 32GB 堆。Tue, 19 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/jvm-%E5%AF%B9%E8%B1%A1%E5%88%9B%E5%BB%BA%E4%B8%8E%E7%94%9F%E5%91%BD%E5%91%A8%E6%9C%9F/https://blog.zoloy.top/posts/jvm-%E5%AF%B9%E8%B1%A1%E5%88%9B%E5%BB%BA%E4%B8%8E%E7%94%9F%E5%91%BD%E5%91%A8%E6%9C%9F/new 指令触发类加载检查、TLAB 无锁分配、零值初始化、设置 Mark Word 与 Klass Pointer 对象头，经历 Eden→Survivor→Old 三代晋升至 GC 回收。Sat, 16 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/jvm-shenandoahgc/https://blog.zoloy.top/posts/jvm-shenandoahgc/Shenandoah 用对象头前 Brooks 转发指针实现并发转移，应用线程每次读引用经过转发指针跳转，CAS 更新实现转移与访问的原子同步。Thu, 14 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/jvm-epsilon%E5%9B%9E%E6%94%B6%E5%99%A8/https://blog.zoloy.top/posts/jvm-epsilon%E5%9B%9E%E6%94%B6%E5%99%A8/Epsilon GC 只分配不回收，消除 GC 变量后可用于 JMH 基准测试、测量 GC 真实开销、通过二分 OOM 边界确定应用精确内存需求。Mon, 11 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/jit%E7%BC%96%E8%AF%91%E4%B8%8E%E9%80%83%E9%80%B8%E5%88%86%E6%9E%90/https://blog.zoloy.top/posts/jit%E7%BC%96%E8%AF%91%E4%B8%8E%E9%80%83%E9%80%B8%E5%88%86%E6%9E%90/C2 逃逸分析将未逃逸对象做标量替换免除堆分配，连带触发锁消除，方法内联为优化提供更大上下文，让 Java 代码越跑越快。Sat, 09 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/graalvm-native-image-aot%E7%BC%96%E8%AF%91%E5%9B%9B%E9%98%B6%E6%AE%B5/https://blog.zoloy.top/posts/graalvm-native-image-aot%E7%BC%96%E8%AF%91%E5%9B%9B%E9%98%B6%E6%AE%B5/Native Image 通过指针分析删死代码、堆快照预计算 Spring 初始化、AOT 编译为机器码，将启动从 12s 压缩到 0.2s。Wed, 06 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/g1%E5%9E%83%E5%9C%BE%E5%9B%9E%E6%94%B6%E5%99%A8-rset/https://blog.zoloy.top/posts/g1%E5%9E%83%E5%9C%BE%E5%9B%9E%E6%94%B6%E5%99%A8-rset/G1 将堆切为 2048 个 Region 动态分代，RSet 记录跨 Region 引用避免全堆扫描，SATB 保留快照保证并发标记不丢对象。Mon, 04 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/%E8%99%9A%E6%8B%9F%E7%BA%BF%E7%A8%8B%E7%9A%84pinning%E9%97%AE%E9%A2%98/https://blog.zoloy.top/posts/%E8%99%9A%E6%8B%9F%E7%BA%BF%E7%A8%8B%E7%9A%84pinning%E9%97%AE%E9%A2%98/synchronized 的 Monitor 锁与 OS 线程绑定导致虚拟线程无法卸载，替换为 ReentrantLock 可彻底解决 Pinning 问题。Fri, 01 Nov 2024 09:00:00 GMThttps://blog.zoloy.top/posts/stream%E6%83%B0%E6%80%A7%E6%B1%82%E5%80%BC%E4%B8%8Esink%E9%93%BE/https://blog.zoloy.top/posts/stream%E6%83%B0%E6%80%A7%E6%B1%82%E5%80%BC%E4%B8%8Esink%E9%93%BE/揭示 Stream 惰性求值机制——中间操作只构建 Pipeline 链表不执行，终止操作触发 Sink 链构建后每个元素一次性穿越所有中间操作，配合短路操作提前终止遍历。Wed, 30 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/lambda%E7%9A%84invokedynamic%E4%B8%8E%E5%8C%BF%E5%90%8D%E5%86%85%E9%83%A8%E7%B1%BB/https://blog.zoloy.top/posts/lambda%E7%9A%84invokedynamic%E4%B8%8E%E5%8C%BF%E5%90%8D%E5%86%85%E9%83%A8%E7%B1%BB/Lambda 通过 invokedynamic 运行时动态生成类，无捕获时为单例，与编译期生成.class 的匿名内部类本质不同Sun, 27 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/java21%E7%BB%93%E6%9E%84%E5%8C%96%E5%B9%B6%E5%8F%91/https://blog.zoloy.top/posts/java21%E7%BB%93%E6%9E%84%E5%8C%96%E5%B9%B6%E5%8F%91/StructuredTaskScope 将子任务生命周期限定在 try-with-resources 花括号内，任一失败全员取消，与虚拟线程配合实现廉价海量并发无泄漏。Fri, 25 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/java-record-sealed%E7%B1%BB/https://blog.zoloy.top/posts/java-record-sealed%E7%B1%BB/Record 一行声明不可变数据类编译器自动生成全套方法，Sealed 限制子类集合配合 switch 模式匹配实现编译期穷举检查消除漏分支。Tue, 22 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/hashmap%E7%9A%84%E5%93%88%E5%B8%8C%E6%89%B0%E5%8A%A8%E4%B8%8E%E6%89%A9%E5%AE%B9%E6%9C%BA%E5%88%B6/https://blog.zoloy.top/posts/hashmap%E7%9A%84%E5%93%88%E5%B8%8C%E6%89%B0%E5%8A%A8%E4%B8%8E%E6%89%A9%E5%AE%B9%E6%9C%BA%E5%88%B6/HashMap 用 h^(h>>>16) 扰动让高位参与桶定位，扩容时 hash&oldCap 一次位运算决定节点去留，尾插法消除 JDK7 死循环。Sun, 20 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/concurrenthashmap-%E6%A1%B6%E7%BA%A7%E9%94%81/https://blog.zoloy.top/posts/concurrenthashmap-%E6%A1%B6%E7%BA%A7%E9%94%81/JDK 8 ConcurrentHashMap 以桶头节点 synchronized + CAS 空桶替代 JDK 7 分段锁，多线程协助扩容，ForwardingNode 让读操作对扩容透明。Thu, 17 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/arraylist-copyonwritearraylist-fail-fast/https://blog.zoloy.top/posts/arraylist-copyonwritearraylist-fail-fast/ArrayList 1.5 倍扩容与 fail-fast 迭代器的 modCount 检测机制，CopyOnWriteArrayList 以写时复制数组实现读无锁写安全。Tue, 15 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/%E6%B3%A8%E8%A7%A3%E5%8E%9F%E7%90%86-%E5%8A%A8%E6%80%81%E4%BB%A3%E7%90%86/https://blog.zoloy.top/posts/%E6%B3%A8%E8%A7%A3%E5%8E%9F%E7%90%86-%E5%8A%A8%E6%80%81%E4%BB%A3%E7%90%86/注解本质是继承 Annotation 的接口，运行时通过 JDK 动态代理将 class 文件属性表中的值映射为方法返回值。Sun, 13 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/%E6%B3%9B%E5%9E%8B%E6%93%A6%E9%99%A4-%E6%A1%A5%E6%8E%A5%E6%96%B9%E6%B3%95/https://blog.zoloy.top/posts/%E6%B3%9B%E5%9E%8B%E6%93%A6%E9%99%A4-%E6%A1%A5%E6%8E%A5%E6%96%B9%E6%B3%95/泛型擦除后多态调用断裂，编译器自动生成桥接方法作为 JVM 与泛型之间的翻译层修复方法签名不匹配。Thu, 10 Oct 2024 09:00:00 GMThttps://blog.zoloy.top/posts/%E5%BA%8F%E5%88%97%E5%8C%96-%E5%8F%8D%E5%BA%8F%E5%88%97%E5%8C%96%E5%BA%95%E5%B1%82/https://blog.zoloy.top/posts/%E5%BA%8F%E5%88%97%E5%8C%96-%E5%8F%8D%E5%BA%8F%E5%88%97%E5%8C%96%E5%BA%95%E5%B1%82/反序列化通过 Unsafe.allocateInstance 绕过构造器恢复对象状态，同时也带来了 RCE 安全风险。Tue, 08 Oct 2024 09:00:00 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