Hi,
I have been trying to get my team to upgrade from version 24.2 for a while. I am very excited about the work being done with the MCP server, so am even more motivated to switch to 25.2.
However, the speed of running our usual script to extract the schema has become much worse in 25.2 compared to 24.2.
The commands we run are:
set ddl tablespace off
set ddl segment_attributes off
lb generate-schema -split -sql -synonyms
A typical output from 24.2 will spend the longest amount of time in the “[Method writeChangeLogs]” procedure, where for a typical run takes 2-3 minutes (the log below was 2min 45sec).
SQLcl: Release 24.2 Production on Sun Aug 03 07:23:34 2025
Copyright (c) 1982, 2025, Oracle. All rights reserved.
Last Successful login time: Wed Nov 08 2023 11:33:20 -08:00
Connected to:
Oracle Database 19c Standard Edition 2 Release 19.0.0.0.0 - Production
Version 19.27.0.0.0
DDL Option TABLESPACE was set to OFF
DDL Option SEGMENT_ATTRIBUTES was set to OFF
--Starting Liquibase at 2025-08-03T07:23:40.772119700 (version 4.25.0 #3966 built at 2023-11-10 23:07:29 UTC)
Export Flags Used:
Export Grants false
Export Synonyms true
[Method loadCaptureTable]:
[Type - TYPE_SPEC]: 1146 ms
[Type - TYPE_BODY]: 201 ms
[Type - SEQUENCE]: 4917 ms
[Type - DIRECTORY]: 117 ms
[Type - CLUSTER]: 1727 ms
[Type - TABLE]: 37888 ms
[Type - MATERIALIZED_VIEW_LOG]: 76 ms
[Type - MATERIALIZED_VIEW]: 18050 ms
[Type - VIEW]: 12082 ms
[Type - REF_CONSTRAINT]: 1834 ms
[Type - DIMENSION]: 79 ms
[Type - PACKAGE_SPEC]: 2490 ms
[Type - FUNCTION]: 330 ms
[Type - PROCEDURE]: 1310 ms
[Type - DB_LINK]: 78 ms
[Type - SYNONYM]: 114 ms
[Type - INDEX]: 4620 ms
[Type - TRIGGER]: 2128 ms
[Type - PACKAGE_BODY]: 9380 ms
[Type - JOB]: 527 ms
[Type - PUBLIC_SYNONYM]: 304 ms
[Method loadCaptureTable]: 99407 ms
[Method sortCaptureTable]: 180 ms
[Method writeChangeLogs]: 164366 ms
Changelog created and written out to file controller.xml
Operation completed successfully.
Disconnected from Oracle Database 19c Standard Edition 2 Release 19.0.0.0.0 - Production
Version 19.27.0.0.0
Unforunately, for 25.2, the typical result for the same is now taking 17-18 minutes (6 times slower).
SQLcl: Release 25.2 Production on Sun Aug 03 07:55:14 2025
Copyright (c) 1982, 2025, Oracle. All rights reserved.
Connected to:
Oracle Database 19c Standard Edition 2 Release 19.0.0.0.0 - Production
Version 19.27.0.0.0
DDL Option TABLESPACE was set to OFF
DDL Option SEGMENT_ATTRIBUTES was set to OFF
--Starting Liquibase at 2025-08-03T07:55:18.738027700 using Java 17.0.16 (version 4.30.0 #0 built at 2025-04-01 10:24+0000)
Export Flags Used:
Export Grants false
Export Synonyms true
[Method loadCaptureTable]:
[Type - TYPE_SPEC]: 730 ms
[Type - TYPE_BODY]: 92 ms
[Type - SEQUENCE]: 4215 ms
[Type - DIRECTORY]: 93 ms
[Type - CLUSTER]: 1218 ms
[Type - TABLE]: 34294 ms
[Type - MATERIALIZED_VIEW_LOG]: 64 ms
[Type - MATERIALIZED_VIEW]: 468 ms
[Type - VIEW]: 9489 ms
[Type - REF_CONSTRAINT]: 1980 ms
[Type - DIMENSION]: 57 ms
[Type - PACKAGE_SPEC]: 2085 ms
[Type - FUNCTION]: 414 ms
[Type - PROCEDURE]: 1437 ms
[Type - DB_LINK]: 69 ms
[Type - SYNONYM]: 171 ms
[Type - INDEX]: 3042 ms
[Type - TRIGGER]: 2235 ms
[Type - PACKAGE_BODY]: 9493 ms
[Type - JOB]: 444 ms
[Type - PUBLIC_SYNONYM]: 313 ms
[Method loadCaptureTable]: 72403 ms
[Method sortCaptureTable]: 204 ms
[Method writeChangeLogs]: 1046125 ms
Changelog created and written out to file controller.xml
Operation completed successfully.
Disconnected from Oracle Database 19c Standard Edition 2 Release 19.0.0.0.0 - Production
Version 19.27.0.0.0
There is of course variation in runs, but I have run these several times and get the same approximate times.
I am extracting for the same database on the same computer, with the same JDK.
Of course I can run the MCP server on 25.2, and do the rest of the work on 24.2, but it would be nice to figure out what happened and how to get everyone on the recent release.
Thank you for any help!
Doug