[Translated from MOS] The V $ undostat view is not updated every 10 minutes, and V $ undostat has only one row (one rows)

The V $ undostat view is not updated every 10 minutes. V $ undostat has only one row (one rows)

Reference Original:
The V $ undostat view is not getting updated in every 10 minutes. (Doc ID 1206365.1)

Applicable:
Oracle Server-Enterprise Edition-version: 10.2.0.1 and later [release: 10.2 and later]
Information in this document applies to any platform.

Symptoms:
The V $ undostat view is not getting updated every 10 minutes.

SQL> select begin_time, end_time, undoblks from V $ undostat;

Begin_time end_time undoblks
--------------------------------------------------
21-aug-2010 03:48:44 07-sep-2010 11:02:14 75016989

Only one row is returned for the preceding query.

Changes:
SQL> sho parameter undo

Name type value
-----------------------------------------------------------------------------
_ In_memory_undo Boolean false
_ Undo_autotune Boolean false ---> pay attention to this row record.
Undo_management string auto
Undo_retention integer 3600
Undo_tablespace string undotbs1

 

The parameter "_ undo_autotune" has been set to false.
This has disabled automatic IC undo tuning.

Solution:

Set "_ undo_autotune" parameter to true:

SQL> alter system set "_ undo_autotune" = true;

This disables the standard tracking of Undo statistics in V $ undostat. You can see only the one row of data as noted in this case.