Sudden Increase in Unformatted Blocks

(Doc ID 469985.1)

Last updated on SEPTEMBER 02, 2017

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 9.2 to 10.2]
Information in this document applies to any platform.
***Checked for relevance on 19-Nov-2010***


Unexplained increases in unformatted blocks in a tablespace. Very few of the unformatted blocks ever get used. More space is added whenever a new block is requested resulting in even more unformatted blocks. The number of unformatted blocks varies from one database to another. Some databases only add a few thousand unformatted blocks at one time. Others add millions of unformatted blocks all at once. Once the problem starts the only way to prevent new unformatted blocks from being added is to rebuild the tablespace.


No changes to environment.


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