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SMON is Generating a Trace File With UNDO SEG (BEFORE RECOVERY) Information (Doc ID 754743.1)

Last updated on SEPTEMBER 23, 2019

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 9.2 to 10.2]
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Information in this document applies to any platform.


A SMON trace is showing the following message:

$ more ORCL_smon_3735640.trc

UNDO SEG (BEFORE RECOVERY): usn = 0 Extent Control Header
Extent Header:: spare1: 0 spare2: 0 #extents: 6 #blocks: 95
last map 0x00000000 #maps: 0 offset: 2080
Highwater:: 0x0040032a ext#: 4 blk#: 9 ext size: 16
#blocks in seg. hdr's freelists: 0
#blocks below: 0
mapblk 0x00000000 offset: 4
Map Header:: next 0x00000000 #extents: 6 obj#: 0 flag: 0x40000000
Extent Map

Is this an actual error or simply an informational message? If informational, how can this be
turned off?


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