1. Chapter 2 Hardware Configuration and Considerations Database Processing Chapter 2

2. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Some consideration for configuration Oracle Architecture Auguste Rodin - The Thinker (1840 - 1917) Hmmm... Stand-alone configuration, use disk arrays, multiple databases, networked hosts?

3. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Page 12 The configuration in our lab Chapter 2 SGA Background Processes (Server) (Database) Single Host Database Files Single, local disk drive

4. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Page 12 Data files spread across multiple disks Chapter 2 SGA Background Processes (Server) (Database) Single Host Data Files 02 Data Files 01 Data Files 03 Disk 0Disk 1Disk 2

5. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Page 12 Shadowed/mirrored data files Chapter 2 SGA Background Processes (Server) (Database) Single Host Data Files 02 Data Files 01 Data Files 03 Disk 0Disk 1Disk 2 Data Files 02 Data Files 01 Data Files 03 Disk 3Disk 4Disk 5 Each file is mirrored

6. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Page 12 Chapter 2 SGA Background Processes (Server) (Database) Single Host Data Files 02 Data Files 01 Data Files 03 Disk 0Disk 1Disk 2 Data Files 02 Data Files 01 Data Files 03 Disk 3Disk 4Disk 5 Shadowed/mirrored data files What is this configuration called? –RAID 1 Advantages? –Backup and performance But shouldn’t it take twice as long to perform each write? That is, isn’t the “write penalty” 100% –No, writes are issued in parallel

7. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Page 12 RAID 5 Chapter 2 SGA Background Processes (Server) (Database) Single Host Disk 0Disk 1Disk 2 Block 0 Block 3 Parity Block 7 Block 2 Parity Block 5 Parity Block 4 Block 6 Block 8

8. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Page 12 Chapter 2 SGA Background Processes (Server) (Database) Single Host Disk 0Disk 1Disk 2 Block 0 Block 3 Parity Block 7 Block 2 Parity Block 5 Parity Block 4 Block 6 Block 8 RAID 5 Blocks of data file are “striped” across multiple disks What is parity for? –The parity information is a derived “check value” that enables the values in a failed disk to be reconstructed. –If drive 2 fails, the parity information on drives 0 and 3 would be used to recalculate the values (degraded mode).

9. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Chapter 2 A stand-alone host can support multiple databases –Oracle 8i has configuration assistant –Not sure about Oracle 8

10. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Chapter 2 Single Host

11. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Stand-alone host Chapter 2 Two databases mounted Two instances

12. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Networked Hosts Chapter 2 The world is not “stand-alone” A review of high-level networking trends...

13. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Mainframes Chapter 2 image source: Oracle8 Certified Professional DBA Certification Exam Guide Hard-wired terminals initially Emulated hard-wired terminal Centralized

14. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Client/Server Chapter 2 image source: Oracle8 Certified Professional DBA Certification Exam Guide PCs, GUIs, and Ethernet technology Decentralized Issues: software distribution scalability platform dependence

15. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Internet Chapter 2 image source: Oracle8 Certified Professional DBA Certification Exam Guide Centralized Multi-tier architectures

16. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Networked Hosts Chapter 2 The database server is one of those tiers Net8 uses Oracle’s Transparent Substrate (TNS) protocol –Allows for remote queries and updates We’ll cover it in detail in Chapter 13

17. Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Networked Hosts Chapter 2 Oracle vs. SQL Server http://www.microsoft.com/sql/techinfo/deployment/2000/MigrateOracle.asp