Parallel DDL causes Capture to Slow Significantly / causes Logminer Spill
(Doc ID 563217.1)
Last updated on FEBRUARY 28, 2019
Applies to:Oracle Database - Enterprise Edition - Version 10.2.0.3 to 220.127.116.11 [Release 10.2 to 11.1]
Oracle Database Cloud Schema 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
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.
NOTE: In the images and/or the document content below, the user information and data used represents fictitious data from the Oracle sample schema(s) or Public Documentation delivered with an Oracle database product. Any similarity to actual persons, living or dead, is purely coincidental and not intended in any manner.
Capture Slows dramatically.
Partition related DDL operation performed such as move partition.
Logminer slows due to spilling to logminer tables.
A typical PDDL activity might be:
alter table ice.alternate_reference move <partition_name>
tablespace <tablespace_name> storage(initial 1k) parallel 16;
The spill is visible in growth of a lob segment associated
with the table : system.logmnr_spill$.
To confirm this issue may be being encountered :
- Capture will be slow ;
- there is likely to be latency in changes being captured;
- there will be significant and increasing growth in the lob segment
determined as follows :
select ds.segment_name, ds.partition_name, ds.segment_type,
ds.tablespace_name, ds.bytes, dl.segment_name, dl.column_name
from dba_segments ds, dba_lobs dl where
ds.segment_name = dl.segment_name and
dl.table_name = 'LOGMNR_SPILL$' and
dl.column_name = 'SPILL_DATA';
As parallel DDL may be associated with very large objects, the above
object may grow in an unbounded fashion.
To view full details, sign in with your My Oracle Support account.
Don't have a My Oracle Support account? Click to get started!
In this Document