IBM 000-8697 Benutzerhandbuch
System Architecture
2-3
Step 3: Locate the Page in Memory . . . . . . . . . . . 2-61
Step 4: Read the Page in from Disk . . . . . . . . . . . 2-62
Steps 5-7: Lock Buffer, Release Lock, and Wake
Step 4: Read the Page in from Disk . . . . . . . . . . . 2-62
Steps 5-7: Lock Buffer, Release Lock, and Wake
Causes of Flushing . . . . . . . . . . . . . . . . . 2-64
Flushing a Full Buffer . . . . . . . . . . . . . . . . 2-65
Flushing a Full Buffer . . . . . . . . . . . . . . . . 2-65
Triple Buffering . . . . . . . . . . . . . . . . . . 2-66
Buffer Contents . . . . . . . . . . . . . . . . . . 2-68
Causes of Flushing . . . . . . . . . . . . . . . . . 2-68
Flushing a Full Buffer . . . . . . . . . . . . . . . . 2-69
Buffer Contents . . . . . . . . . . . . . . . . . . 2-68
Causes of Flushing . . . . . . . . . . . . . . . . . 2-68
Flushing a Full Buffer . . . . . . . . . . . . . . . . 2-69
Initiating a Checkpoint . . . . . . . . . . . . . . . 2-70
Fast Recovery. . . . . . . . . . . . . . . . . . . 2-71
Archive Checkpoints . . . . . . . . . . . . . . . . 2-71
Fast Recovery. . . . . . . . . . . . . . . . . . . 2-71
Archive Checkpoints . . . . . . . . . . . . . . . . 2-71
What Happens During a Checkpoint . . . . . . . . . . . . 2-72
When the Daemons Flush the Buffer Pool . . . . . . . . . . 2-73
How OnLine Synchronizes Buffer Flushing. . . . . . . . . . 2-74
Write Types Describe Flushing Activity . . . . . . . . . . . 2-75
When the Daemons Flush the Buffer Pool . . . . . . . . . . 2-73
How OnLine Synchronizes Buffer Flushing. . . . . . . . . . 2-74
Write Types Describe Flushing Activity . . . . . . . . . . . 2-75
Sorted Write . . . . . . . . . . . . . . . . . . . 2-76
Idle Write . . . . . . . . . . . . . . . . . . . . 2-76
Foreground Write . . . . . . . . . . . . . . . . . 2-77
LRU Write . . . . . . . . . . . . . . . . . . . . 2-77
Chunk Write . . . . . . . . . . . . . . . . . . . 2-77
Big-Buffer Write . . . . . . . . . . . . . . . . . . 2-78
Idle Write . . . . . . . . . . . . . . . . . . . . 2-76
Foreground Write . . . . . . . . . . . . . . . . . 2-77
LRU Write . . . . . . . . . . . . . . . . . . . . 2-77
Chunk Write . . . . . . . . . . . . . . . . . . . 2-77
Big-Buffer Write . . . . . . . . . . . . . . . . . . 2-78