<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[万物皆可互联，一切均可编程]]></title><description><![CDATA[学如逆水行舟，不进则退]]></description><link>https://blog.youkuaiyun.com/qq_29630271</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; qq_29630271]]></copyright><item><title><![CDATA[arthas使用]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/160315510</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/160315510</guid><author>qq_29630271</author><pubDate>Sun, 19 Apr 2026 23:11:04 +0800</pubDate><description><![CDATA[【代码】arthas使用。]]></description><category></category></item><item><title><![CDATA[Java 分析工具]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/160275645</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/160275645</guid><author>qq_29630271</author><pubDate>Sat, 18 Apr 2026 15:51:44 +0800</pubDate><description><![CDATA[【代码】Java 分析工具。]]></description><category></category></item><item><title><![CDATA[TDengine学习]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/159618569</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/159618569</guid><author>qq_29630271</author><pubDate>Sun, 29 Mar 2026 22:40:06 +0800</pubDate><description><![CDATA[TDengine是一款专为时序数据优化的数据库，采用超级表+子表模型设计，主键为时间戳+标签组合。核心优势包括：1)按时间分片存储提升压缩率；2)设备级子表隔离减少查询扫描；3)顺序写磁盘加速写入；4)内置聚合函数降低计算负载；5)无事务锁机制实现高并发。典型表设计包含时间戳字段、可变数据字段和TAG标签，建议一类数据建一个超级表，一个设备对应一张子表。通过列式存储和时间分区等优化，TDengine能实现百倍于传统数据库的时序数据处理性能。]]></description><category></category></item><item><title><![CDATA[RocketMQ使用]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/157843883</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/157843883</guid><author>qq_29630271</author><pubDate>Sat, 07 Feb 2026 18:17:39 +0800</pubDate><description><![CDATA[版本：RocketMQ 4.9.8端口：9876（NameServer）、10911（Broker）]]></description><category></category></item><item><title><![CDATA[JVM调优]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/157648736</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/157648736</guid><author>qq_29630271</author><pubDate>Mon, 02 Feb 2026 13:50:15 +0800</pubDate><description><![CDATA[本文总结了Java 8环境下JVM调优参数配置建议。主要内容包括：通用调优参数（堆内存、新生代/老年代比例等）；推荐G1 GC作为主流选择（适合4G以上堆、低延迟场景），提供关键参数配置；CMS GC作为备选方案（适合小堆、老系统）；以及默认Parallel GC的适用场景（仅推荐离线计算）。文章对比了不同回收器的优缺点，建议90%生产服务优先采用G1，CMS仅适用于特定兼容场景，Parallel GC仅适合无延迟要求的后台处理。]]></description><category></category></item><item><title><![CDATA[缓存问题相关]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/156825731</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/156825731</guid><author>qq_29630271</author><pubDate>Sun, 11 Jan 2026 12:01:02 +0800</pubDate><description><![CDATA[]]></description><category></category></item><item><title><![CDATA[MySQL调优实践]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/156237175</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/156237175</guid><author>qq_29630271</author><pubDate>Wed, 24 Dec 2025 17:29:18 +0800</pubDate><description><![CDATA[【代码】MySQL调优实践。]]></description><category></category></item><item><title><![CDATA[MySQL 的 MVCC（多版本并发控制）详解]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/155893774</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/155893774</guid><author>qq_29630271</author><pubDate>Sat, 13 Dec 2025 23:06:18 +0800</pubDate><description><![CDATA[核心组件：隐藏列、undo log、Read View、事务 ID；核心价值：读写分离，提升并发性能，保证事务隔离性；关键差异：不同隔离级别的 Read View 生成时机决定了隔离性表现；适用场景：快照读（普通 SELECT），当前读仍需锁配合。理解 MVCC 是掌握 InnoDB 事务、隔离级别、锁机制的关键，也是优化 MySQL 高并发性能的基础。]]></description><category></category></item><item><title><![CDATA[mysql的快照读和当前读]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/155888864</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/155888864</guid><author>qq_29630271</author><pubDate>Sat, 13 Dec 2025 15:52:42 +0800</pubDate><description><![CDATA[MySQL InnoDB引擎中的快照读和当前读是两种核心读操作模式。快照读通过MVCC机制读取历史版本，无锁且读写不阻塞，适用于普通查询；当前读则加锁读取最新数据，确保强一致性，适用于更新/删除等操作。二者的差异体现在数据版本、加锁行为、并发特性和适用场景上。快照读牺牲数据&quot;最新性&quot;换取高并发，当前读牺牲&quot;并发性&quot;保证数据准确性。隔离级别会影响这两种读模式的表现，开发者应根据业务需求选择合适的读方式。]]></description><category></category></item><item><title><![CDATA[openssl命令使用]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/155568541</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/155568541</guid><author>qq_29630271</author><pubDate>Thu, 04 Dec 2025 13:27:27 +0800</pubDate><description><![CDATA[使用windows openssl命令生成私钥时，报错Can’t open C:\Program Files\Common Files\ssl/openssl.cnf for reading, No such file or directory。原因是openssl.cnf文件不存在，创建一个该文件就可以了。]]></description><category></category></item><item><title><![CDATA[密码学基础]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/155206848</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/155206848</guid><author>qq_29630271</author><pubDate>Tue, 25 Nov 2025 13:52:33 +0800</pubDate><description><![CDATA[本文概述了密码学中的核心概念与技术。对称密码包括分组密码（AES、DES/3DES）及其五种工作模式（ECB、CBC、CFB、OFB、CTR），以及流密码RC4。非对称密码使用公钥/私钥对（RSA、ECC）。消息认证、单向散列函数（MD5、SHA1）和数字签名技术（RSA等算法）分别确保完整性、认证和不可否认性。文章还介绍了PKI体系、两种数字签名方式（直接签名和散列值签名），以及四种典型密码攻击（COA、KPA、CPA、CCA）。最后列举了PBE、IV、KDC等专业术语。]]></description><category></category></item><item><title><![CDATA[TCP/IP 五层协议栈]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/154407388</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/154407388</guid><author>qq_29630271</author><pubDate>Tue, 04 Nov 2025 22:02:49 +0800</pubDate><description><![CDATA[本文概要介绍了计算机网络协议栈核心层的格式规范。传输层详细解析了TCP头部结构，包括20字节的固定头部（含端口号、序列号、窗口大小等10个字段）及选项字段（MSS、窗口缩放、时间戳等）。网络层描述了IPv4报头格式，包含20字节固定部分（版本、头部长度、协议类型等）和最多40字节的可选字段。数据链路层未展开说明。全文重点突出了各层协议关键字段的字节位置、长度和功能，为理解网络协议封装提供了结构化参考。]]></description><category></category></item><item><title><![CDATA[linux IO多路复用]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/153703414</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/153703414</guid><author>qq_29630271</author><pubDate>Tue, 21 Oct 2025 21:59:28 +0800</pubDate><description><![CDATA[【代码】linux IO多路复用。]]></description><category></category></item><item><title><![CDATA[可靠的tcp连接]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/153530827</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/153530827</guid><author>qq_29630271</author><pubDate>Sat, 18 Oct 2025 20:35:09 +0800</pubDate><description><![CDATA[]]></description><category></category></item><item><title><![CDATA[tcp三次握手和四次挥手]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/153193053</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/153193053</guid><author>qq_29630271</author><pubDate>Mon, 13 Oct 2025 13:52:22 +0800</pubDate><description><![CDATA[发送 SYN 报文（同步自身序列号）+ ACK 报文（确认客户端 SYN）TIME_WAIT 等待 2*MSL（最大报文段寿命，约1-4分钟）应用层调用 close()，发送 FIN 报文（剩余数据已发完）执行 connect()，发送 SYN 报文（同步序列号）执行 socket()/bind()/listen()应用层调用 close()，触发 FIN 报文。发送 ACK 报文（确认服务器 SYN）接收 FIN 报文，内核自动回复 ACK。接收 FIN 报文，回复 ACK。接收 SYN+ACK 报文。]]></description><category></category></item><item><title><![CDATA[go工程实践]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/151231447</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/151231447</guid><author>qq_29630271</author><pubDate>Fri, 05 Sep 2025 21:45:52 +0800</pubDate><description><![CDATA[清理未使用的包，下载需要的包。编译windows可执行文件。]]></description><category></category></item><item><title><![CDATA[haproxy安装和使用]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/151155016</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/151155016</guid><author>qq_29630271</author><pubDate>Wed, 03 Sep 2025 18:55:33 +0800</pubDate><description><![CDATA[【代码】haproxy安装和使用。]]></description><category></category></item><item><title><![CDATA[ssh端口转发详解]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/149490339</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/149490339</guid><author>qq_29630271</author><pubDate>Mon, 21 Jul 2025 00:20:35 +0800</pubDate><description><![CDATA[【代码】ssh端口转发详解。]]></description><category></category></item><item><title><![CDATA[再生龙备份和恢复硬盘]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/149295895</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/149295895</guid><author>qq_29630271</author><pubDate>Sat, 12 Jul 2025 16:19:34 +0800</pubDate><description><![CDATA[【代码】再生龙备份和恢复硬盘。]]></description><category></category></item><item><title><![CDATA[spring自动装配常用注解]]></title><link>https://blog.youkuaiyun.com/qq_29630271/article/details/145282328</link><guid>https://blog.youkuaiyun.com/qq_29630271/article/details/145282328</guid><author>qq_29630271</author><pubDate>Tue, 21 Jan 2025 14:41:53 +0800</pubDate><description><![CDATA[spring框架常用注解]]></description><category></category></item></channel></rss>