https://major.io/2010/12/07/tap-into-your-linux-system-with-systemtap/ December 7, 2010 By Major Hayden 4 Comments One of the most interesting topics I’ve seen so far during my RHCA training at Rackspace this week isSystemTap. In short, SystemTap all…
写在前面:本文是对OSCon09的<Linux System and Performance Monitoring>一文的学习笔记,主要内容是总结了其中的要点,以及加上了笔者自己的一些理解.通过总结,一方面是为了加深笔者自己的理解,另一方面也是希望能对有需要的朋友有所帮助. 做为一名服务器开发工程师,经常会有分析系统性能,解决系统性能瓶颈的需求.通常我们所说的性能问题,不外乎就是CPU/Memory/IO/Network这四个方面,这四个方面每个都有各自独特之处,同时也都是相互关联的.下面就分…
source: http://linoxide.com/linux-shell-script/shell-script-check-linux-system-health/ This article introduces a shell script to perform linux system health check.This script collects system information and status like hostname, kernel version, uptim…
The frequently used operation in Linux system 2017-04-08 12:48:09 1. mount the hard disk: #: fdisk -l %% use this operation to check how many and what disk it found in the computer. #: mkdir yiDongYingPan %% mkdir a new file as the locatio…
http://www.cyberciti.biz/tips/reboot-or-halt-linux-system-in-emergency.html Linux kernel includes magic system request keys. It was originally developed for kernel hackers. However, you can use this hack to reboot, shutdown or halt computer safely (r…
2014-06-11 Check the Linux system log find the errorr: Jun 9 11:18:49 hostname avahi-daemon[3640]: Invalid query packet. Jun 9 11:19:29 hostnam elast message repeated 7 times Jun 9 11:22:06 hostnam eavahi-daemon[3640]: Invalid query packet. Jun…
Linux System linux 是一个功能强大的操作系统,同时它是一个自由软件,是免费的.源代码开放的,编制它的目的是建立不受任何商品化软件版权制约的.全世界都能自由使用的UNIX兼容产品.各种使用 Linux 作为内核的 GNU 操作系统正被广泛地使用著:虽然这些系统通常被称作为“Linux”,但是它们应该更精确地被称为 GNU/Linux 系统 .…
1. The Stat Family #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> int stat(const char *path, struct stat *buf); int fstat(int fd, struct stat *buf); int lstat(const char *path, struct stat *buf); struct stat{ dev_t…
system(3) - Linux man page Name system - execute a shell command Synopsis #include <stdlib.h> int system(const char *command); Description system() executes a command specified in command by calling /bin/sh -c command, and returns after the command…
1. 内核提供三种不同的方式来记录时间 Wall time (or real time):actual time and date in the real world Process time:the time that a process spends executing on a processor 包括用户时间user time 和 系统时间system time Monotonic time:use the system's uptime (time since boot) for th…
1. 进程调度 the process scheduler is the component of a kernel that selects which process to run next. 进程调度器需要使 处理器使用率最大化,并且提供 使多个进程并发执行的虚拟 Deciding which processes run, when, and for how long is the process scheduler's fundamental responsibility. 时间…
1. Scatter/Gather I/O a single system call to read or write data between single data stream and multiple buffers This type of I/O is so named because the data is scattered into or gathered from the given vector of buffers Scatter/Gather I/O 相比于 C标准…
