System Analysis and Tuning Guide

An administrator's guide for problem detection, resolution and optimization. Find how to inspect and optimize your system by means of monitoring tools and how to efficiently manage resources. Also contains an overview of common problems and solutions and of additional help and documentation resources.

SUSE Linux Enterprise Server is used for a broad range of usage scenarios in enterprise and scientific data centers. SUSE has ensured SUSE Linux Enterprise Server is set up in a way that it accommodates different operation purposes with optimal performance. However, SUSE Linux Enterprise Server must meet very different demands when employed on a number crunching server compared to a file server, for example.

It is not possible to ship a distribution that is optimized for all workloads. Different workloads vary substantially in some aspects. Most important among those are I/O access patterns, memory access patterns, and process scheduling. A behavior that perfectly suits a certain workload might reduce performance of another workload. For example, I/O-intensive tasks, such as handling database requests, usually have completely different requirements than CPU-intensive tasks, such as video encoding. The versatility of Linux makes it possible to configure your system in a way that it brings out the best in each usage scenario.

This manual introduces you to means to monitor and analyze your system. It describes methods to manage system resources and to tune your system. This guide does not offer recipes for special scenarios, because each server has got its own different demands. It rather enables you to thoroughly analyze your servers and make the most out of them.

General Notes on System Tuning

Tuning a system requires a carefully planned proceeding. Learn which steps are necessary to successfully improve your system.

Section II, System Monitoring

Linux offers a large variety of tools to monitor almost every aspect of the system. Learn how to use these utilities and how to read and analyze the system log files.

Section III, Kernel Monitoring

The Linux kernel itself offers means to examine every nut, bolt and screw of the system. This part introduces you to SystemTap, a scripting language for writing kernel modules that can be used to analyze and filter data. Collect debugging information and find bottlenecks by using kernel probes, and Perf. Last, monitor applications with Oprofile.

Section IV, Resource Management

Learn how to set up a tailor-made system fitting exactly the server's need. Get to know how to use power management while at the same time keeping the performance of a system at a level that matches the current requirements.

Section V, Kernel Tuning

The Linux kernel can be optimized either by using sysctl, via the /proc and /sys file systems or by kernel command line parameter. This part covers tuning the I/O performance and optimizing the way how Linux schedules processes. It also describes basic principles of memory management and shows how memory management could be fine-tuned to suit needs of specific applications and usage patterns. Furthermore, it describes how to optimize network performance.

Section VI, Handling System Dumps

This part enables you to analyze and handle application or system crashes. It introduces tracing tools such as strace or ltrace and describes how to handle system crashes using Kexec and Kdump.

HINT: Getting the SUSE Linux Enterprise SDK

The SDK is a module for SUSE Linux Enterprise and is available via an online channel from the SUSE Customer Center. Alternatively, go to http://download.suse.com/, search for SUSE Linux Enterprise Software Development Kit and download it from there. Refer to Section 13.0, Installing Modules, Extensions, and Third Party Add-On Products, (↑Deployment Guide) for details.

Many chapters in this manual contain links to additional documentation resources. This includes additional documentation that is available on the system and documentation available on the Internet.

For an overview of the documentation available for your product and the latest documentation updates, refer to http://www.suse.com/doc or to the following section:

Available Documentation

We provide HTML and PDF versions of our books in different languages. The following manuals for users and administrators are available for this product:

Installation Quick Start, (↑Quick Start Manuals)

Lists the system requirements and guides you step-by-step through the installation of SUSE Linux Enterprise Server from DVD, or from an ISO image.

Deployment Guide, (↑Deployment Guide)

Shows how to install single or multiple systems and how to exploit the product inherent capabilities for a deployment infrastructure. Choose from various approaches, ranging from a local installation or a network installation server to a mass deployment using a remote-controlled, highly-customized, and automated installation technique.

Administration Guide, (↑Administration Guide)

Covers system administration tasks like maintaining, monitoring and customizing an initially installed system.

Virtualization Guide, (↑Virtualization Guide)

Describes virtualization technology in general, and introduces libvirt—the unified interface to virtualization—and detailed information on specific hypervisors.

Storage Administration Guide, (↑Storage Administration Guide)

Provides information about how to manage storage devices on a SUSE Linux Enterprise Server.

AutoYaST, (↑AutoYaST)

AutoYaST is a system for installing one or more SUSE Linux Enterprise Server systems automatically and without user intervention, using an AutoYaST profile that contains installation and configuration data. The manual guides you through the basic steps of auto-installation: preparation, installation, and configuration.

Security Guide, (↑Security Guide)

Introduces basic concepts of system security, covering both local and network security aspects. Shows how to use the product inherent security software like AppArmor or the auditing system that reliably collects information about any security-relevant events.

Security and Hardening Guide, (↑Security and Hardening Guide)

Deals with the particulars of installing and setting up a secure SUSE Linux Enterprise Server, and additional post-installation processes required to further secure and harden that installation. Supports the administrator with security-related choices and decisions.

System Analysis and Tuning Guide

An administrator's guide for problem detection, resolution and optimization. Find how to inspect and optimize your system by means of monitoring tools and how to efficiently manage resources. Also contains an overview of common problems and solutions and of additional help and documentation resources.

Subscription Management Tool for SLES 12 SP2, (↑Subscription Management Tool for SLES 12 SP2)

An administrator's guide to Subscription Management Tool—a proxy system for SUSE Customer Center with repository and registration targets. Learn how to install and configure a local SMT server, how to mirror and manage repositories, how to manage client machines, and how to configure clients to use SMT.

GNOME User Guide, (↑GNOME User Guide)

Introduces the GNOME desktop of SUSE Linux Enterprise Server. It guides you through using and configuring the desktop and helps you perform key tasks. It is intended mainly for end users who want to make efficient use of GNOME as their default desktop.

Find HTML versions of most product manuals in your installed system under /usr/share/doc/manual. The latest documentation updates are available at http://www.suse.com/documentation/ where you can download the documentation for your product in various formats.

Feedback

Several feedback channels are available:

Bugs and Enhancement Requests

For services and support options available for your product, refer to http://www.suse.com/support/.

To report bugs for a product component, go to https://scc.suse.com/support/requests, log in, and click Create New.

User Comments

We want to hear your comments about and suggestions for this manual and the other documentation included with this product. Use the User Comments feature at the bottom of each page in the online documentation or go to http://www.suse.com/documentation/feedback.html and enter your comments there.

Mail

For feedback on the documentation of this product, you can also send a mail to doc-team@suse.com. Make sure to include the document title, the product version and the publication date of the documentation. To report errors or suggest enhancements, provide a concise description of the problem and refer to the respective section number and page (or URL).

Documentation Conventions

The following notices and typographical conventions are used in this documentation:

  • /etc/passwd: directory names and file names

  • PLACEHOLDER: replace PLACEHOLDER with the actual value

  • PATH: the environment variable PATH

  • ls, --help: commands, options, and parameters

  • user: users or groups

  • package name : name of a package

  • Alt, Alt+F1: a key to press or a key combination; keys are shown in uppercase as on a keyboard

  • File, File > Save As: menu items, buttons

  • This paragraph is only relevant for the AMD64/Intel 64 architecture. The arrows mark the beginning and the end of the text block.

    This paragraph is only relevant for the architectures z Systems and POWER. The arrows mark the beginning and the end of the text block.

  • Dancing Penguins (Chapter Penguins, ↑Another Manual): This is a reference to a chapter in another manual.

  • Commands that must be run with root privileges. Often you can also prefix these commands with the sudo command to run them as non-privileged user.

    command
    sudo command
  • Commands that can be run by non-privileged users.

                  
                  command
                
  • Notices

    WARNING: Warning Notice

    Vital information you must be aware of before proceeding. Warns you about security issues, potential loss of data, damage to hardware, or physical hazards.

    IMPORTANT: Important Notice

    Important information you should be aware of before proceeding.

    NOTE: Note Notice

    Additional information, for example about differences in software versions.

    HINT: Tip Notice

    Helpful information, like a guideline or a piece of practical advice.