Undo tablespace usage
The undo tablespace is a very important tablespace in Oracle databases, and its usage is also the focus of DBAs. However, in busy production systems, it is easy to see that the undo tablespace usage is very high, or even 100%. So how big should the undo tablespace be set? How is an undo block allocated? What should I do when the undo tablespace usage is very high? This article describes the above issues.
1. undo tablespace size settings
1. First, the size of an undo tablespace is preset based on the database and business conditions;
2. After the database runs for a period of time, you can estimate the reasonable undo tablespace size as follows:
Calculation formula: UR * (USP * DBS)
UR indicates the value of the undo_retention parameter.
UPS indicates the number of undo blocks generated per second.
DBS indicates the size of database blocks.