03 2013 档案
摘要:转自http://ifeve.com/cpu-cache-flushing-fallacy-cn/即使是资深的技术人员,我经常听到他们谈论某些操作是如何导致一个CPU缓存的刷新。看来这是关于CPU缓存如何工作和缓存子系统如何与执行核心交互的一个常见误区。本文将致力于解释CPU缓存的功能以及执行程序指令的CPU核心如何与缓存交互。我将以最新的Intel x86 CPU为例进行说明,其他CPU也使用相似技术以达到相同目的。绝大部分常见的现代系统都被设计成在多处理器上共享内存。共享内存的系统都有一个单独的内存资源,它会被两个或者更多的独立CPU核心同时访问。核心到主存的延迟变化范围很大,大约在10-
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摘要:http://duartes.org/gustavo/blog/category/software-illustrated/page/2Motherboard Chipsets and the Memory MapI’m going to write a few posts about computer internals with the goal of explaining how modern kernels work. I hope to make them useful to enthusiasts and programmers who are interested in this
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摘要:http://duartes.org/gustavo/blog/post/what-your-computer-does-while-you-waitWhat Your Computer Does While You Wait当你等待时,计算机在做什么?This post takes a look at the speed – latency and throughput – of various subsystems in a modern commodity PC, an Intel Core 2 Duo at 3.0GHz. I hope to give a feel for the r
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摘要:经常听到系统架构、软件架构、信息架构、数据架构等等,那么怎么去区分这些概念呢?附录http://www.codingthearchitecture.com/pages/book/types-of-architecture.htmlTypes of architectureTreat enterprise architectures with a pinch of saltArchitecture applies to various aspects of software systems development, understandably so given its generic and
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摘要:摘自http://www.gosoa.com.cn/mysql-%E9%94%81%E8%A1%A8%E6%9C%BA%E5%88%B6%E5%88%86%E6%9E%90为了给高并发情况下的mysql进行更好的优化,有必要了解一下mysql查询更新时的锁表机制。一、概述MySQL有三种锁的级别:页级、表级、行级。MyISAM和MEMORY存储引擎采用的是表级锁(table-level locking);BDB存储引擎采用的是页面锁(page-levellocking),但也支持表级锁;InnoDB存储引擎既支持行级锁(row-level locking),也支持表级锁,但默认情况下是采用行级
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