When you make log backups, the log area is not stored as a whole, but in backup units called log segments.
The size of the log segments is determined by the general database parameter LOG_SEGMENT_SIZE. It is unrelated to the size of the individual log volumes, but may not exceed the total of all log volumes.
Select the size in such a way as to ensure that enough space remains after a log segment has been backed up, in order to include any changes that have just been made.
User Defined Value |
Log Segment Size Used by the System |
Log segment size not defined (LOG_SEGMENT_SIZE = 0) |
1/3 of the total log area |
Log segment size in pages less than/equal to 50% of the total log area |
The value defined for LOG_SEGMENT_SIZE |
Log segment size > 50% of the total log area |
50% of the log area |
See also:
Concepts of the Database System