Front cover Eserver IBM pSeries Sizing and Capacity Planning A Practical Guide Discover the concepts and approach to perform sizing and capacity planning Learn how to size the new systems Understand capacity planning and upgrades G. Benton Gibbs Jerry M. Enriquez Nigel Griffiths Corneliu Holban Eunyoung Ko Yohichi Kurasawa ibm.com/redbooks International Technical Support Organization IBM Eserver pSeries Sizing and Capacity Planning: A Practical Guide March 2004 SG24-7071-00 Note: Before using this information and the product it supports, read the information in “Notices” on page xi. First Edition (March 2004) This edition applies to the sizing and capacity planning of IBM Eserver pSeries and RS/6000 servers as configured and used with AIX 5L and Linux operating systems. © Copyright International Business Machines Corporation 2004. 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 . xi Trademarks . xii Preface . xiii The team that wrote this redbook. xiii Become a published author . xvii Comments welcome. xviii Part 1. Introduction to sizing and capacity planning. 1 Chapter 1. Overview, concepts, and approach. 3 1.1 Definitions of common terms. 4 1.2 Concepts . 4 1.2.1 Required knowledge and experience . 5 1.2.2 Sizing with capacity planning . 5 1.2.3 The sizing problem . 5 1.2.4 Sizing inputs . 6 1.2.5 Sizing outputs . 7 1.2.6 Who performs sizing . 9 1.3 Sizing and resizing process. 9 1.3.1 System design and requirements . 10 1.3.2 Sizing model . 10 1.3.3 Hardware requirements. 11 1.3.4 Building block choices. 11 1.3.5 eConfig for the price . 13 1.3.6 Sales, purchase, install, and production . 13 1.3.7 Gathering performance data . 13 1.3.8 Performance tuning. 13 1.3.9 Estimated or measured growth . 14 1.3.10 Capacity planning . 14 1.3.11 Resizing model . 14 1.3.12 rPerf reliance. 15 1.4 Weighing sizing components. 16 1.4.1 Memory size . 16 1.4.2 Disk type and number . 17 1.4.3 Adapters for disk, tape and network . 17 1.4.4 Software . 17 1.4.5 Summary. 18 1.5 The importance of the right amount of information . 18 © Copyright IBM Corp. 2004. All rights reserved. iii 1.5.1 Brain overload . 19 1.5.2 Summary. 21 1.6 A practical sizing method . 21 1.6.1 Segmentation . 21 1.7 Performance theory. 25 1.8 General rules of thumb for RDBMS memory. 27 1.8.1 Application resident set . 27 1.8.2 RDBMS data and file system cache . 28 1.8.3 RDBMS utilization rules of thumb . 28 1.8.4 Utilization. 29 1.8.5 RDBMS raw data to disk rules of thumb . 30 1.8.6 RDBMS disk use rules of thumb . 32 1.9 The performance saturation curve . 32 1.10 Successive approximation and sizing levels . 35 1.11 Plagiarism . 36 1.12 Triangulation . 37 1.12.1 A triangulation story . 39 1.13 Common sizing mistakes . 40 1.13.1 Sizing report outline . 41 1.13.2 A sizing story. 41 1.14 The eConfig configurator. 42 1.14.1 Configurator test . 43 1.15 Cost-based sizing method. 45 1.16 High availability and disaster recovery . 45 1.17 Capacity Upgrade on Demand . 47 1.18 Sizing for Linux on pSeries . 48 Part 2. Components involved in sizing and capacity planning. 51 Chapter 2. Hardware components . 53 2.1 Performance methodology . 54 2.2 Overview of pSeries systems . 57 2.2.1 Autonomic computing . 59 2.2.2 e-business on demand . 60 2.2.3 Reliability, availability, and serviceability features. 62 2.2.4 Capacity Upgrade on Demand . 64 2.3 pSeries processors . 66 2.3.1 Processor descriptions . 68 2.3.2 RISC/CISC concepts. 68 2.3.3 Superscalar architecture: Pipelines and parallelisms . 70 2.3.4 32-bit versus 64-bit computing . 71 2.3.5 Performance of processors . 72 2.3.6 Processor evolution. 74 iv IBM Eserver pSeries Sizing and Capacity Planning 2.4 Memory . 84 2.4.1 Memory hierarchy . 84 2.4.2 Locality concept . 86 2.4.3 Caches . 87 2.4.4 Memory cycles . 90 2.4.5 Virtual memory concepts. 91 2.4.6 Memory affinity . 94 2.4.7 Large page support . ..