1.系统进程 2.系统资源管理 3.作业管理 4.用户管理 5.文件权限 6.别名定义       一.系统进程 1.进程的定义 进程是操作系统的概念,每当我们执行一个程序时,对于操作系统来讲就创建了一个进程,在这个过程中,伴随着资源的分配和释放.可以认为进程是一个程序的一次执行过程. 实际上,当计算机开机的时候,内核(kernel)只建立了一个init进程.Linux内核并不提供直接建立新进程的系统调用.剩下的所有进程都是init进程通过fork机制建立的.新的进程要通过老的进程复制自身得到,…

对客户DB进行巡检,发现TOP EVENT是LOG FILE Sequential read 等待事件说明 https://www.xuebuyuan.com/zh-hant/1743045.html 這個等待事件通常發生在對redo log信息進行讀取的時候,比如在線redo的歸檔操作,ARCH進程需要讀取redo log的信息,用於redo log的信息是順序寫入的,所以在讀取的時候也是安裝順序的方式來讀取的. 也就是说在日志切换时!归档的产生需要顺序读日志文件!产生的等待事件,那么可能的问…

从远程仓库pull下来的代码有两个类类名首字母小写出现如下情况 然后我想删了重新写一下(就是把这个类删了,代码复制到名字正确的类里面),然后commit的时候出现这个错误,后来删一个commit一下,就可以commit,暂时估计是删了之后commit把原先index里面的清空了…

A path to the file is constructed by merely adding a URI to the value of the root directive. If a URI has to be modified, the alias directive should be used Syntax: alias path; Default: — Context: location Defines a replacement for the specified loca…

引用于文章https://blog.csdn.net/line_aijava/article/details/71473793 root: Sets the root directory for requests. For example, with the following configuration location /i/ { root /data/w3; }//The /data/w3/i/top.gif file will be sent in response to the “/i…

centos6.5/centos7系统中,alias定义在/etc/bashrc,分别写在/etc/profile.d/*.sh中,可以在此目录添加my.sh,或者~/.bashrc,或者~/.bash_profile alias cp='cp -i'alias ll='ls -l --color=auto'alias rm='rm -i'alias mv='mv -i' alias attrib='chmod'alias cd..='cd ..'alias chdir='cd'alias cl…

root介绍 Syntax: root path; Default: root html; Context: http, server, location, if in location Sets the root directory for requests. For example, with the following configuration 访问 http://localhost:80/i/top.gif,nginx匹配的文件路径是/data/w3/i/top.gif locatio…

I’ve always been frustrated in Visual Studio (all versions I can remember including latest vs2012) with not being able to look at the top of a file and edit the bottom.  Recently, on an Microsoft insiders list I participate in, someone posted that ex…

Few days ago,I opened the Genesys demo VM by VMware Server 1.0.4 and got an error like this: "Configuration file was created by a VMware product with more features than this version" may be a correct statement, The VM image was created by a high…

文件包含漏洞 目录遍历漏洞在国内外有许多不同的叫法,也可以叫做信息泄露漏洞.非授权文件包含漏洞等. 文件包含分类 LFI:本地文件包含(Local File Inclusion) RFI:远程文件包含(Remote File Inclusion) 与文件包含有关的函数 include():只有代码执行到该函数时才会包含文件进来,发生错误时只给出一个警告并继续向下执行. include_once():和 include()功能相同,区别在于当重复调用同一文件时,程序只调用一次. require()…

进程管理工具uptime,top,htop 一uptime 显示当前时间,系统已启动的时间.当前上线人数,系统平均负载(1.5.10分钟的平均负载,一般不会超过1) 系统平均负载:指在特定时间间隔内运行队列中的平均进程数 通常每个CPU内核的当前活动进程数不大于3,那么系统的性能良好. 如果每个CPU内核的任务数大于5,那么此主机的性能有严重问题 如果linux主机是1个双核CPU,当Load Average 为6的时候说明机器已经被充分使用 [root@centos72 ~]# uptime…

原文地址:https://docker.github.io/compose/compose-file/ Compose file reference The Compose file is a YAML file defining services, networks and volumes. The default path for a Compose file is./docker-compose.yml. A service definition contains configuratio…

Background C++ is one of the main development languages used by many of Google's open-source projects. As every C++ programmer knows, the language has many powerful features, but this power brings with it complexity, which in turn can make code more…

CoffeeScript is a little language that compiles into JavaScript. Underneath that awkward Java-esque patina, JavaScript has always had a gorgeous heart. CoffeeScript is an attempt to expose the good parts of JavaScript in a simple way. The golden rule…

mmet Documentation Syntax Child: > nav>ul>li <nav> <ul> <li></li> </ul> </nav> Sibling: + div+p+bq <div></div> <p></p> <blockquote></blockquote> Climb-up: ^ div+div>p>s…

Emmet Documentation Syntax   Child: > nav>ul>li <nav> <ul> <li></li> </ul> </nav> Sibling: + div+p+bq <div></div> <p></p> <blockquote></blockquote> Climb-up: ^ div+div>p&g…

Directives(指令) Syntax(语法): aio on | off | threads[=pool]; Default: aio off; Context: http, server, location This directive appeared in version 0.8.11. 指令出现在版本0.8.11版本 Enables or disables the use of asynchronous file I/O (AIO) on FreeBSD and Linux: 启用…

src:http://docs.emmet.io/cheat-sheet/ Emmet Documentation Syntax   Child: > nav>ul>li <nav> <ul> <li></li> </ul> </nav> Sibling: + div+p+bq <div></div> <p></p> <blockquote></blo…

Contents Introduction Background Hello Closure World Dependency Management Making an AJAX call with Google Closure Closure Templates Using plovr to Simplify Closure Development More Closure Templates Animations in Google Closure Using plovr for Produ…

转自:http://www.raywenderlich.com/32963/apple-push-notification-services-in-ios-6-tutorial-part-2 Update 4/12/2013: Fully updated for iOS 6 (original post byMatthijs Hollemans, update by Ali Hafizji). This is the second part of a 2-part tutorial series…

最近在学习使用Scala语言做项目,感觉这门语言实在是太优美了!作为一个本科数学.研究生机器学习专业的混合人才(哈哈),这门语言真的是满足了普通计算机编程(告诉计算机怎么做)和函数式编程(告诉计算机做什么)的所有幻想.学了半个多月,根本停不下来!先来做个总结: 语法简洁,往往比Java少至少一半的代码量.比如: 支持自动类型判断,可以省去很多类型标志. e.g.  val x = 2 用伴生对象来生成类,省去new的麻烦.e.g. val cat = Cat("Hello Ketty"…

Linux Essentials Certification Globbing ls ?.txt --- ? stands for one character while * means one or more characters ls [F]*.txt --- list file starting with F ls [F]*.txt --- list file starting with F ls f[igh] --- the first character is f, but the s…

1:怎么获取Markup.cpp 和 Markup.h 首先到http://www.firstobject.com/dn_markup.htm链接下,下载Release 11.5 zip (579k)C++ source code for Linux, Mac, Windows,解压后里面是一个Test文件夹和Markup.cpp和Markup.h文件,将Markup.h和Markup .cpp拷贝并添加到工程中,第一次编译可能会出现预编译错误,解决的方法在Markup.cpp最前面includ…

Google C++ Style Guide   Table of Contents Header Files Self-contained Headers The #define Guard Forward Declarations Inline Functions Names and Order of Includes Scoping Namespaces Unnamed Namespaces and Static Variables Nonmember, Static Member, an…

Redis 5.0 release notes ======================= -------------------------------------------------------------------------------- Upgrade urgency levels: LOW: No need to upgrade unless there are new features you want to use. MODERATE: Program an upgra…

语法 Child: > nav>ul>li <nav> <ul> <li></li> </ul> </nav> Sibling: + div+p+bq <div></div> <p></p> <blockquote></blockquote> Climb-up: ^ div+div>p>span+em^bq <div>&l…

by Umer Zeeshan Ijaz The purpose of this tutorial is to introduce students to the frequently used tools for NGS analysis as well as giving experience in writing one-liners. Copy the required files to your current directory, change directory (cd) to t…

Hyperpolyglot.org From Hyperpolyglot.org C++ Style Languages: C++, Objective-C, Java, C# a side-by-side reference sheet grammar and invocation | variables and expressions | arithmetic and logic | strings | regexes | dates and time arrays | dictionari…

openvpn Section: Maintenance Commands (8)Index NAME openvpn - secure IP tunnel daemon. SYNOPSIS openvpn [ options ... ]  INTRODUCTION OpenVPN is an open source VPN daemon by James Yonan. Because OpenVPN tries to be a universal VPN tool offering a gre…

find命令使用技巧 查找文件,移动到某个目录 使用find和xargs 15条 linux Find 命令实际使用方法 find 命令用法 find命令使用经验 find用法小结 find与xargs的用法------实际例子(ZT) find命令使用技巧 1.查找文件 Linux中查找文件的命令为“find”命令,syntax: find [起始目录] 寻找条件 操作 如,从根目录下开始查找abc.cpp文件  find / -name abc.cpp  在当前目录下所有.cpp文件  fi…