Chapter 2 Hardware Configuration and Considerations Database Processing Chapter 2

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

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

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

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

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

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

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).

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

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

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

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...

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

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

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

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

Copyright © 2001 Harold Pardue, University of South AlabamaChapter 2 Networked Hosts Chapter 2 Oracle vs. SQL Server