ramdisk

I am studying the boot process in Linux. I came across this sentence "RAM is several orders of magnitude faster than a floppy disk, so system operation is fast from a ramdisk" The kernel will anyway load the root filesystem in RAM for executing it. So my question why do we need a ramdisk for loading the the root filesystem, if the kernel loads the root file system into RAM ? The documentation for SUSE Linux provides a good explanation of why Linux is booted with a RAMDisk: As soon as the Linux kernel has been booted and the root file system (/) mounted, programs can be run and further kernel

Duplicate: RAMDrive for compiling - is there such a thing? I have an idea how to speed up my IDE. I want to create a RAM disk and move my solution onto this virtual disk. I think that this can speed up the IDE because RAM is much faster than a HDD. Has anyone done this before? PS: I think, when I have some documents in my program(real world) which are used frequently(for example some document templates) it could be good idea to move these documents onto a RAM disk as well to speed up I/O. Am I wrong? If power is a problem, a UPS could solve it. I just read a post on this very subject: http:/

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Does OS X (Snow Leopard in particular) have an equivalent to (some versions of) Linux's /dev/shm , ie something where you can write to and read from a file without necessarily touching the hard drive? 回答1: You can create and mount a ram based disk as follows: Create a disk $ hdiutil attach -nomount ram://$((2 * 1024 * SIZE_IN_MB)) hdiutil will return the name of the ramdisk. Format and mount the disk diskutil eraseVolume HFS+ RAMDisk NAME_OF_DISK Creating a 100MB ramdisk: $ hdiutil attach -nomount ram://$((2 * 1024 * 100)) /dev/disk3 $

在学习Android软件安全的过程中，经常要用到Android的动态调试。但是呢，一般的Android应用在发布的时候都是发布版的不能直接被调试，为了能使Android应用能够支持调试就需要对Android应用进行解包以及打包加android:debuggable="true"属性处理，比较烦的是有时候一些Android应用加了对抗的处理，并不能顺利打包处理，这就纠结了。 @根据android的官方文档，如果要调试一个App里面的dex代码，必须满足以下两个条件中的任何一个： 1.App的AndroidManifest.xm中Application标签必选包含属性android:debuggable="true"； 2./default.prop中ro.debuggable的值为1。 由于正常的软件发布时都不会把android:debuggable设置为true，所以要达成条件1）需要对app进行重新打包，这不仅每次分析一个App都重复操作，而且很多软件会对自身进行校验，重打包后执行会被检测到，所以想办法满足第2）个条件是个一劳永逸的办法，我实际使用的方法就是满足第二个条件。由于default.prop是保存在boot.img的ramdisk中，这部分每次重新启动都会重新从rom中加载，所以要到目的必须修改boot.img中的ramdisk并重新刷到设备中

1. LMB (logical memory blocks) lmb为uboot下的一种内存管理机制，用于管理镜像的内存。lmb所记录的内存信息最终会传递给kernel。在/include/lmb.h和/lib/lmb.c中有对lmb的接口和定义的具体描述。 lmb_init() 对lmb进行初始化，初始化后相应内存就归lmb管辖。 参考： https://blog.csdn.net/machiner1/article/details/47805069 介绍：LMB 2. FDT， uboot中对FDT的支持 参考： https://blog.csdn.net/eleven_xiy/article/details/72835181 介绍：FDT， 3. FIT 参考： http://www.wowotech.net/u-boot/fit_image_overview.html (u-boot FIT image介绍) 参考： https://blog.csdn.net/ooonebook/article/details/53495002 （bootm跳转到kernel流程1） 参考： https://blog.csdn.net/ooonebook/article/details/53495021 （bootm跳转到kernel流程2） 介绍：bootm_headers_t， 4.

I have a program that is very heavily hitting the file system, reading and writing to a set of working files. The files are several gigabytes in size, but not so large as to not fit on a RAM-disk. The machines this program runs on are typically Ubuntu Linux boxes. Is there a way to configure the file manager to have a very very large cache, and even to cache writes so they hit the disk later? Or is there a way to create a RAM disk that writes-through to real disk? By default, Linux will use free RAM (almost all of it) to cache disk accesses, and will delay writes. The heuristics used by the