Book Image

CentOS Quick Start Guide

By : Shiwang Kalkhanda
Book Image

CentOS Quick Start Guide

By: Shiwang Kalkhanda

Overview of this book

Linux kernel development has been the worlds largest collaborative project to date. With this practical guide, you will learn Linux through one of its most popular and stable distributions. This book will introduce you to essential Linux skills using CentOS 7. It describes how a Linux system is organized, and will introduce you to key command-line concepts you can practice on your own. It will guide you in performing basic system administration tasks and day-to-day operations in a Linux environment. You will learn core system administration skills for managing a system running CentOS 7 or a similar operating system, such as RHEL 7, Scientific Linux, and Oracle Linux. You will be able to perform installation, establish network connectivity and user and process management, modify file permissions, manage text files using the command line, and implement basic security administration after covering this book. By the end of this book, you will have a solid understanding of working with Linux using the command line.
Table of Contents (11 chapters)

Monitoring processes and load averages

The load average is the average of the load for a given period of time on each CPU. It takes into account the following:

  • Actively running processes (including each thread as an individual, separate task) on a CPU core.

  • Runnable processes, waiting for a CPU to become available.

  • Sleeping processes, for example, waiting for some kind of resource (generally disk I/O or network I/O) to become available.

  • Linux counts each physical CPU core and microprocessor hyper-thread as separate execution units, and refers to them as individual CPUs. Each CPU has an independent request queue. We can count the total number of system CPUs using by the following command:

    $ grep "model name" /proc/cpuinfo | wc -l

Understanding load averages on Linux...