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Database
Chapter
Processing
2
Chapter 2
Hardware Configuration and
Considerations
Some consideration for
configuration
Hmmm... Stand-alone
Oracle Architecture
configuration, use disk arrays,
multiple databases, networked
hosts?
Auguste Rodin - The Thinker
(1840 - 1917)
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 2
Stand-alone host
Chapter 2
• The configuration in our lab
Single Host
SGA
(Server)
(Database)
Page 12
Background Processes
Database Files
Single, local disk drive
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 2
Stand-alone host
Chapter 2
• Data files spread across multiple
disks
Single Host
SGA
(Server)
(Database)
Page 12
Background Processes
Data
Files 01
Data
Files 02
Data
Files 03
Disk 0
Disk 1
Disk 2
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 2
Stand-alone host
Chapter 2
• Shadowed/mirrored data files
Single Host
SGA
(Server)
(Database)
Page 12
Background Processes
Data
Files 01
Data
Files 02
Data
Files 03
Data
Files 01
Data
Files 02
Data
Files 03
Disk 0
Disk 3
Copyright © 2001 Harold Pardue, University of South Alabama
Disk 1
Disk 4
Disk 2
Each file is
mirrored
Disk 5
Chapter 2
Stand-alone host
Chapter 2
• Shadowed/mirrored data files
• What is this
configuration called?
Single Host
– RAID 1
•
Advantages?
(Server)
SGA
– Backup and Background
performance
Processes
• But shouldn’t it take twice as long to
perform each
write?
Data
Data That is,
Data isn’t
Files 01
Files 02
Files 03
the
“write
penalty”
100%
Disk 0
Disk 1
Disk 2
(Database)
Data
Data
Data
– No, writes
issued
in parallel
Filesare
01
Files 02
Files 03
Page 12
Disk 3
Copyright © 2001 Harold Pardue, University of South Alabama
Disk 4
Disk 5
Chapter 2
Stand-alone host
Chapter 2
• RAID 5
Single Host
SGA
(Server)
(Database)
Page 12
Background Processes
Block 0
Block 3
Block 2
Parity
Parity
Block 4
Parity
Block 7
Block 5
Parity
Block 6
Block 8
Disk 0
Copyright © 2001 Harold Pardue, University of South Alabama
Disk 1
Disk 2
Chapter 2
Stand-alone host
Chapter 2
• RAID 5
• Blocks of data file are “striped”
Single Host
across multiple
disks
• What is parity for?SGA
(Server)
– The parity information is a derived
Background
Processes
“check value”
that enables
the values in a
failed disk to be reconstructed.
– If drive 2
fails, theBlockparity
information
Block 0
2
Parity
on drivesBlock
0 3and 3 would
be used
Parity
Block 4 to
Parity
Block 5
Block 6
(Database)
recalculate
the
values
(degraded
Block 7
Parity
Block 8 mode).
Page 12
Disk 0
Copyright © 2001 Harold Pardue, University of South Alabama
Disk 1
Disk 2
Chapter 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 Alabama
Chapter 2
Stand-alone host
Chapter 2
Single Host
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 2
Stand-alone host
Chapter 2
Two databases
mounted
Two instances
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 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 Alabama
Chapter 2
Mainframes
Chapter 2
Centralized
Hard-wired
terminals initially
Emulated
hard-wired
terminal
image source: Oracle8 Certified Professional
DBA Certification Exam Guide
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 2
Client/Server
Chapter 2
Decentralized
PCs, GUIs, and
Ethernet
technology
Issues:
software distribution
scalability
platform dependence
image source: Oracle8 Certified Professional
DBA Certification Exam Guide
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 2
Internet
Chapter 2
Centralized
Multi-tier architectures
image source: Oracle8 Certified Professional
DBA Certification Exam Guide
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 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 Alabama
Chapter 2
Networked Hosts
Chapter 2
• Oracle vs. SQL Server
http://www.microsoft.com/sql/techinfo/deployment/2000/MigrateOracle.asp
Copyright © 2001 Harold Pardue, University of South Alabama
Chapter 2