Virtual data optimizer VDO for advanced storage management in linux

preface We have introduced the logical volume manager LVM before. Its main function is to scale the file system, so that people can use disk space more flexibly. However, the emergence of LVM can not solve the problem of data optimization. There are often some duplicate data or empty blocks on our devices, which will greatly waste our di ...

Posted by Zyx on Sun, 19 Sep 2021 01:59:03 +0200

Linux device tree < reprint >

Reprint address: http://blog.csdn.net/smcdef/article/details/77387975 1. Introduction to device tree Linus Torvalds declared in the ARM Linux mailing list on March 17, 2011 that "this whole ARM thing is a fusing pain in the ass", which triggered an earthquake in the ARM Linux community, and then the ARM community made a s ...

Posted by MidOhioIT on Sat, 18 Sep 2021 14:54:26 +0200

Summary of computer three-level Linux application and development technology -- user management

Basic concepts: Linux system supports multiple users to log in at the same time. Different users can perform different tasks without affecting each other. User group Is a logical set of users with the same characteristics. For example, create a group, and then put all users who need to access this file into this group, then the users in the ...

Posted by Boris Senker on Sat, 18 Sep 2021 14:44:19 +0200

Installing Mysql on Linux

Reference article: Installing mysql on linux_ Stupid food first fly blog - CSDN blog_ Installing mysql on linux Modify password reference article: What if mysql forgets the password under linux - big no - blog Garden To install Mysql: centos7 MySQL installation (full version)_ Programmer's advanced road - CSDN blog_ Installing MySQL in CentOS ...

Posted by dsp77 on Sat, 18 Sep 2021 07:59:00 +0200

Linux C language plays linked list in mmap mapping

1, Role of mmap mmap function is actually mapping physical address to virtual address, which can be operated by the process in user space, and plays the role of virtual real address conversion; For a simple example, if some records are easy to change and you want to keep them after the program exits, you can use mmap at this time. After resta ...

Posted by gimzo on Sat, 18 Sep 2021 01:23:28 +0200

[CEPH] / etc / init.d/ceph: OSD. 1 not found (/ etc / CEPH / ceph.conf definitions, / var / lib / CEPH definitions) solution

Error reporting description The status of a stored osd is down, but when we start this osd, the following error will be reported [in fact, this osd must exist] [root@stor-21 ~]# service ceph start osd.1 /etc/init.d/ceph: osd.1 not found (/etc/ceph/ceph.conf defines , /var/lib/ceph defines ) Information verification osd status Command: ...

Posted by olsrey on Fri, 17 Sep 2021 14:41:42 +0200

Shell Scripting Tricks - Here Document Free Interaction and Expect Automation Interaction

Preface In a real production environment, writing shell scripts will inevitably encounter some interactive interfaces, such as raid s and extensions, which require interaction, so we need to use the following non-interactive operations to achieve true shell script automation. 1. Here Document exempt from interaction 1. Overview Provide ...

Posted by PHPHorizons on Wed, 15 Sep 2021 18:38:33 +0200

Summary of common Linux shell commands

0 Preface Because I often run various experimental tests in Linux, in order to reduce energy, I usually write the script of automatic running experiment and the script of result processing first, and finally open the experimental results directly with excel. In order to facilitate readers and write scripts in the future, the common instruc ...

Posted by kulin on Wed, 15 Sep 2021 02:34:35 +0200

Raspberry pie linux led character device driver (traditional)

  for any peripheral driver under Linux, it is necessary to configure the corresponding hardware registers. Therefore, the LED driver finally configures the IO port of raspberry pie, but writing the driver under Linux should comply with the linux driver framework. 1, Raspberry pie GPIO 1.1 register address The CPU of raspberry pie 3B is ...

Posted by ec on Tue, 14 Sep 2021 01:24:32 +0200

Phased summary of shell programming + several shell script examples

        I've been learning shell for some time. I've sorted out some basic shell syntax before. Today I'll make a phased summary. In addition, there are several script examples for your reference. Summary brain map Script instance 1. Judge whether the two hosts are ping ed #!/bin/env bash #This script is used to deter ...

Posted by fangfang on Sat, 11 Sep 2021 06:31:41 +0200