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目录 . 简介 . 进程虚拟地址空间 . 内存映射的原理 . 数据结构 . 对区域的操作 . 地址空间 . 内存映射 . 反向映射 .堆的管理 . 缺页异常的处理 . 用户空间缺页异常的校正 . 内核缺页异常 . 在内核和用户空间之间复制数据 1. 简介 用户层进程的虚拟地址空间是Linux的一个重要抽象,它向每个运行进程提供了同样的系统视图,这使得多个进程可以同时运行,而不会干扰到其他进程内存中的内容,此外,它容许使用各种高级的程序设计技术,如内存映射,学习虚拟内存,同样需要考察可用物理内存中…

Page Cache This is used to speed up access to images and data on disk. As pages are read into memory from disk they are cached in the page cache. If they were discarded and then needed again they can quickly be fetched from this cache. 页缓存,为了加速从硬盘当中读…

查看ADDM(数据库版本为ORACLE 10.2.0.5.0)报告时,发现其中有个结论非常不靠谱:Significant virtual memory paging was detected on the host operating system,具体内容如下所示: FINDING 2: 100% impact (3930 seconds) ------------------------------------- Significant virtual memory paging was d…

Understanding Virtual Memory by Norm Murray and Neil Horman Introduction Definitions The Life of a Page Tuning the VM Example Scenarios Further Reading About the Author Introduction One of the most important aspects of an operating system is the Virt…

众所周知,Redis是一个内存数据库,和Memcached类似,所有数据存在内存中,当然,Redis有rdb和appendonlyfile两个落地文件,可以对断电停机等故障下的数据恢复做一些保证.但是到2.0版本之前,Redis的所有数据在运行时都完全是内存读写. 然而在可见的未来,Redis的官网上已经有关于2.0最重要功能的预告,那就是Redis Virtual Memory. 在2.0的测试版本中已经包含VM的测试版代码,但实际上此功能已经比较成熟.使用方法是将配置文件中的vm-enabl…

https://hoytech.com/vmtouch/ [root@localhost ~]# git clone git://github.com/hoytech/vmtouch.git 正克隆到 'vmtouch'... remote: Counting objects: , done. remote: Total (delta ), reused (delta ), pack 接收对象中: ), 285.79 KiB | 24.00 KiB/s, 完成. 处理 delta 中: ), 完…

This has been a long-standing complaint with Java, but it's largely meaningless, and usually based on looking at the wrong information. The usual phrasing is something like "Hello World on Java takes 10 megabytes! Why does it need that?" Well, h…

墙外通道:http://thinkiii.blogspot.com/2014/02/arm64-linux-kernel-virtual-address-space.html Now let's talk about the Linux kernel virtual address space on 64-bit ARM CPU. You can find information about ARMv8 in ARM official website. http://www.arm.com/pr…

http://thinkiii.blogspot.jp/2014/02/arm32-linux-kernel-virtual-address-space.html   The 32-bit ARM CPU can address up to 2^32 = 4GB address*. It's not big enough in present days, since the size of available DRAM on computing devices is growing fast a…