<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Latch Free on Greatfinish Blog</title><link>https://greatfinish.top/tags/latch-free/</link><description>Recent content in Latch Free on Greatfinish Blog</description><generator>Hugo -- gohugo.io</generator><language>zh-cn</language><copyright>© 2026 Greatfinish Blog · [沪ICP备2026022892号](https://beian.miit.gov.cn/)</copyright><lastBuildDate>Wed, 10 Jun 2026 16:30:00 +0800</lastBuildDate><atom:link href="https://greatfinish.top/tags/latch-free/index.xml" rel="self" type="application/rss+xml"/><item><title>记一次由 SQL 执行计划异常引发的高 CPU 与 cache buffers chains 竞争故障处理</title><link>https://greatfinish.top/posts/oracle-sql-plan-high-cpu-cbc-latch/</link><pubDate>Wed, 10 Jun 2026 16:30:00 +0800</pubDate><guid>https://greatfinish.top/posts/oracle-sql-plan-high-cpu-cbc-latch/</guid><description>一次 Oracle SQL 执行计划异常故障复盘：多个 w3wp.exe 会话集中执行 SQL_ID 4ja6bgs1su89c，child 21 选择低选择性 DEALID 索引，导致约 29.7 亿逻辑读、CPU 接近 100%、latch free 与 cache buffers chains 竞争。最终通过固定好计划、清理坏游标、创建复合索引并收集统计信息恢复稳定。</description><media:content xmlns:media="http://search.yahoo.com/mrss/" url="https://greatfinish.top/posts/oracle-sql-plan-high-cpu-cbc-latch/featured.jpg"/></item></channel></rss>