Enabling Flashback – Be Cautious

Enabling flashback on 11.2.0.4 database can take minutes and cause multiple database wait events degrading database performance. On a quite busy system, during the low peak hours, I tried to enable flashback on 11.2.0.4.6 version database and multiple sessions waited on 1. buffer exterminate 2. enq: SQ - contention 3. latch: cbc contention 4. SGA: … Continue reading Enabling Flashback – Be Cautious

Oracle ASMLib

This blog post is more of a note for myself on configuring ASMLib. ASMLib is an optional utility that can be used on Linux systems to manage Oracle ASM devices. ASMLib consists of the following components: An open source (GPL) kernel module package: kmod-oracleasm An open source (GPL) utilities package: oracleasm-support A closed source (proprietary) … Continue reading Oracle ASMLib

latch: cache buffers chains and rollback

I had an interesting encounter with latch: cbc contention early this week. During my oncall I received page for Load of 206.81 exceeded threshold of 150. After I logged into server , the server load average was continously increasing and all the top PIDs were of oracle processes. After logging into database, I saw multiple … Continue reading latch: cache buffers chains and rollback

ORDIM – Oracle Multimedia – Invalid after upgrade

ORDIM - The Oracle Multimedia component might be in INVALID state after the database upgrade to 12c. While I was testing the upgrade on test server, received below errors after the catctl.pl completion. Serial Phase #:69 Files: 1 Use of uninitialized value $gsRTInclusion in concatenation (.) or string at catctl.pl line 1500. Time: 49s ------------------------------------------------------ … Continue reading ORDIM – Oracle Multimedia – Invalid after upgrade

ORA-00353: log corruption near block change time – 11.2.0.3

Recently I came across "ORA-00353: log corruption near block change time" error. Errors in file /oracle/app/diag/rdbms/test/test/trace/test_ms00_54284.trc (incident=1490189): ORA-00353: log corruption near block change time ORA-00353: log corruption near block 4631374 change 263470473806052 time 04/16/2015 06:53:16 ORA-00312: online log 43 thread 3: '+REDO02/test/onlinelog/group_43.258.875922665' ORA-00312: online log 43 thread 3: '+REDO01/test/onlinelog/group_43.258.875922633' Incident details in: /oracle/app/diag/rdbms/test/test/incident/incdir_1490189/test_ms00_54284_i1490189.trc Thu Apr … Continue reading ORA-00353: log corruption near block change time – 11.2.0.3

ORA-01628: max # extents (32765) reached for rollback segment _SYSSMUxxx

Recently I came across "ORA-01628: max # extents (32765)" error. The database had resumable_timeout parameter set I received page for a session in resumable state. Looking into the alert log showed statement in resumable session 'User USER_E3(375), Session 9028, Instance 1' was suspended due to ORA-01628: max # extents (32765) reached for rollback segment _SYSSMU375_247595031$ … Continue reading ORA-01628: max # extents (32765) reached for rollback segment _SYSSMUxxx

ORA-17629 ORA-20079

Yesterday I received page for " ORA-17629: Cannot connect to the remote database server"  reported in Primary Database alert log. Fri Apr 10 06:47:41 2015 Errors in file /oracle/app/diag/rdbms/testdb/testdb/trace/testdb_ora_161991.trc: ORA-17627: ORA-17629: Cannot connect to the remote database server Errors in file /oracle/app/diag/rdbms/testdb/testdb/trace/testdb_ora_161991.trc: ORA-17629: Cannot connect to the remote database server ORA-17627: ORA-17629: Cannot connect to … Continue reading ORA-17629 ORA-20079

Primary on FileSystem and Standby on ASM

For one of the client, standby server went down. We had another standby server which was kept down for more than a month. Decision was taken to start the server and apply incremental SCN based backup on the standby database. The standby was on ASM and the Primary on filesystem.Incremental backup was started from the … Continue reading Primary on FileSystem and Standby on ASM

ORA-00600: [ktbdchk1: bad dscn]

Last week I had performed switchover activity of database on version 11.2.0.3 The switchover was performed using dgmgrl "swicthover to standby" command. After sometime we started receiving "ORA-00600: [ktbdchk1: bad dscn]" on the primary database. Tue Dec 16 10:33:26 2014 Errors in file /ora_software/diag/rdbms/db02_dbv/dbv/trace/db02_ora_16271.trc (incident=434103): ORA-00600: internal error code, arguments: [ktbdchk1: bad dscn], [], [], … Continue reading ORA-00600: [ktbdchk1: bad dscn]

Upgrading to 11.2.0.4 – Dictionary View Performing Poor

Just a quick blog post on things you might see after upgrading to 11.2.0.4. We recently upgraded database from 11.2.0.3 to 11.2.0.4 and query on some data dictionary views ran too slow. 1. Performace of query on dba_free_space degraded 2. Performance of query involving dba_segments is slow DEV01> select ceil(sum(b.bytes)/1024/1024) b from sys.dba_free_space b; Elapsed: … Continue reading Upgrading to 11.2.0.4 – Dictionary View Performing Poor