Front cover Tuning Linux OS on System p The POWER of Innovation Linux kernel tuning DB2, WebSphere, and Oracle tuning SystemTap examples Stephen Hochstetler Kraml Liu Andre Metelo Prasanna S Panchamukhi John Zucker ibm.com/redbooks International Technical Support Organization Tuning Linux OS on IBM System p The POWER of Innovation June 2007 SG24-7338-00 Note: Before using this information and the product it supports, read the information in “Notices” on page ix. First Edition (June 2007) This edition applies to Red Hat Enterprise Linux AS 4 and SUSE Linux Enterprise Server 10. © Copyright International Business Machines Corporation 2007. All rights reserved. Note to U.S. Government Users Restricted Rights -- Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Notices . ix Trademarks . x Preface . xi The team that wrote this book . xi Become a published author . xiv Comments welcome. xv Chapter 1. Introduction to the book. 1 1.1 Operating an efficient server: four phase . 2 1.2 Performance tuning guidelines . 3 1.3 Using information from the System p Performance Lab . 3 1.4 Linux Technology Center . 5 1.5 Understanding the organization of this book . 5 Chapter 2. IBM System p hardware . 7 2.1 System p advantages . 8 2.1.1 Performance . 8 2.1.2 Scalability . 9 2.1.3 Reliability, availability, and serviceability. 11 2.1.4 Manageability . 13 2.1.5 Virtualization . 14 2.2 System p product line introduction . 15 2.2.1 POWER servers . 16 2.2.2 PowerPC servers and blades . 23 2.2.3 IntelliStation. 25 2.2.4 Others . 27 2.3 Server subsystems . 30 2.3.1 Processor subsystem . 30 2.3.2 Memory subsystem . 39 2.3.3 Disk subsystem . 42 2.3.4 Network subsystem. 44 Chapter 3. System p server virtualization. 49 3.1 System p virtualization capabilities introduction . 50 3.2 The POWER Hypervisor . 51 3.3 Logical partitioning on System p . 54 3.3.1 Basic types of logical partitions . 55 3.3.2 Partitions isolation and security. 56 © Copyright IBM Corp. 2007. All rights reserved. iii 3.3.3 Micro-partitions . 56 3.3.4 I/O virtualization . 58 3.3.5 Benefits of partitioning. 58 3.4 Virtual I/O Server (VIOS). 60 3.4.1 Virtual adapters . 61 3.4.2 Benefits of Virtual I/O Server. 63 3.5 Integrated Virtualization Manager and Hardware Management Console . 64 3.5.1 Integrated Virtualization Manager basics . 64 3.5.2 Choosing IVM or HMC to manage your system . 65 3.6 Considerations at the operating system and application level . 66 Chapter 4. Linux . 67 4.1 What is Linux. 68 4.1.1 Historical perspective . 69 4.1.2 The Linux distributions . 71 4.1.3 The Linux Standard Base project . 72 4.2 Why Linux . 73 4.2.1 The open source software advantage. 73 4.2.2 Return of Investment. 75 4.2.3 IBM and open source . 75 4.3 Why Linux on System p. 77 4.3.1 How Linux runs on System p servers . 77 4.3.2 Linux on System p scalability . 78 4.3.3 Linux for System p and Reliability, Availability, and Serviceability . 80 4.3.4 Virtualization and partitioning capabilities . 83 4.3.5 Industry proven architecture . 83 4.3.6 End-to-end solutions and support . 84 Chapter 5. Linux monitoring tools. 87 5.1 Universal system monitoring tool: SystemTap . 88 5.1.1 Getting started. 89 5.1.2 Demo examples . 91 5.1.3 SystemTap Tapset . 96 5.1.4 Creating SystemTap scripts . 97 5.2 CPU utilization monitoring tools . 105 5.2.1 uptime . 105 5.2.2 top . 106 5.2.3 nmon . 107 5.2.4 mpstat . 109 5.3 Memory monitoring tools . 111 5.3.1 vmstat . 111 5.3.2 top . 112 5.3.3 pmap . 112 iv Tuning Linux OS on IBM System p 5.3.4 free . 115 5.4 Network monitoring tools. 116 5.4.1 netstat . 116 5.4.2 traceroute . 118 5.4.3 iptraf . 119 5.4.4 Ethreal. 122 5.5 Disk I/O monitoring tools . 127 5.5.1 iostat . 127 5.6 Miscellaneous monitoring tools . ..