DB2 II: Performance Monitoring, Tuning and Capacity Planning Guide

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DB2 II: Performance Monitoring, Tuning and Capacity Planning Guide Front cover DB2 II: Performance Monitoring, Tuning and Capacity Planning Guide DB2 Information Integrator V8.2 performance drivers and best practices Performance problem determination scenarios Capacity planning Nagraj Alur Miriam Goodwin Hajime Kawada Roger Midgette DB Shenoy Ron Warley ibm.com/redbooks International Technical Support Organization DB2 II: Performance Monitoring, Tuning and Capacity Planning Guide November 2004 SG24-7073-00 Note: Before using this information and the product it supports, read the information in “Notices” on page xv. First Edition (November 2004) This edition applies to Version 8, Release 2 of DB2 Information Integrator (product number 5724-C74). © 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 Figures . vii Tables . ix Examples. xi Notices . xv Trademarks . xvi Preface . xvii The team that wrote this redbook. xvii Become a published author . xx Comments welcome. xx Chapter 1. DB2 Information Integrator architecture overview . 1 1.1 Introduction . 2 1.2 Current business trends . 2 1.2.1 From on demand to grid computing . 3 1.2.2 From grid computing to data federation . 4 1.2.3 From data federation to information integration . 5 1.3 IBM’s DB2 Information Integration overview . 6 1.3.1 Data consolidation or placement. 8 1.3.2 Distributed access (federation) . 9 1.3.3 DB2 Information Integrator products . 9 1.4 DB2 Information Integrator V8.2 . 11 1.4.1 DB2 II V8.2 overview. 11 1.4.2 DB2 II components . 15 1.4.3 Configuring the federated system . 18 1.4.4 Performance considerations . 24 1.5 DB2 Information Integrator topology considerations . 26 1.5.1 Dedicated federated server. 28 1.5.2 Collocated federated server . 28 Chapter 2. Introduction to performance management. 31 2.1 Introduction . 32 2.2 Performance management . 32 2.3 Types of monitoring. 35 2.3.1 Routine monitoring . 35 2.3.2 Online/realtime event monitoring . 36 © Copyright IBM Corp. 2004. All rights reserved. iii 2.3.3 Exception monitoring. 37 2.4 Problem determination methodology. 37 Chapter 3. Key performance drivers of DB2 II V8.2 . 41 3.1 Introduction . 42 3.2 Compilation flow of a federated query. 44 3.3 Execution flow of a federated query . 50 3.4 Key performance drivers . 54 3.4.1 Performance factors . 57 3.4.2 Federated server considerations. 60 3.4.3 Data source considerations. 102 3.4.4 Efficient SQL queries . 109 3.4.5 Hardware and network . 112 Chapter 4. Performance problem determination scenarios . 115 4.1 Introduction . 116 4.2 DB2 II hypotheses hierarchy . 119 4.2.1 DB2 II federated database server resource constraints . 123 4.2.2 DB2 II resource constraints. 124 4.2.3 Federated server or remote data source. 136 4.2.4 Federated server related. 152 4.2.5 Remote data source related . 161 4.3 Monitoring best practices . 162 4.3.1 Performance considerations . 164 4.3.2 Best practices . 165 4.4 Problem scenarios. 167 4.4.1 Federated test environment . 167 4.4.2 Missing or incorrect statistics/index information . 170 4.4.3 Poorly tuned sort heap and buffer pools . 206 4.4.4 Missing or unavailable MQTs . 210 4.4.5 Incompatible data types on join columns . 239 4.4.6 Pushdown problems . 272 4.4.7 Default DB2_FENCED wrapper option with DPF . 339 Chapter 5. Capacity planning in an existing DB2 II environment . 377 5.1 Introduction . 378 5.2 Capacity planning assumptions. 378 5.3 Capacity planning procedure. 379 5.3.1 Capacity planning procedure overview . 381 5.4 Capacity planning new applications . 427 5.4.1 Model of different profiles of queries . 427 5.4.2 Determine new application workload . 428 5.4.3 Estimate capacity for the new application . 428 iv DB2 II: Performance Monitoring, Tuning and Capacity Planning Guide Appendix A. DB2 II V8.2 performance enhancements . 429 Introduction. 430 Fenced wrappers . 430 Parallelism enhancements . 432 Intra-partition parallelism in a non-DPF environment . 432 Inter-partition parallelism in a DPF environment with local data . 433 Inter-partition parallelism in a DPF environment without local data . 434 Updating nickname statistics . 436 Cache tables . 436 Informational constraints . 438 Snapshot monitor support . 439 Health Center alerts . 439 Appendix B. DB2 EXPLAIN facility with DB2 Information Integrator . 441 Brief review of the DB2 EXPLAIN facility . 442 db2exfmt overview . 448 EXPLAIN INSTANCE section . 449 SQL STATEMENT section . 450 Access plan graph. 453 OPERATOR DETAILS section . 455 Objects section . ..
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