10500 event tracking of SMON Processes

10500 event tracking SMON process is a key process in ORACLE. It is responsible for INSTANCE rediscovery, clearing temporary segments, merging idle space, shrinking rollback segments, and maintaining the SMON_SCN_TIME table. We can track the above behavior through the 10500 event: www.2cto.com Level: <= 5 trace instance recovery> 5 trace posting of SMON first enable a SESSION to delete some data SQL> delete test; 48875 rows have been deleted. Www.2cto.com SQL> C:> sqlplus/as sysdba SQL * Plus: Release 10.2.0.1.0-Production on Monday January 21 18:00:40 2013 Copyright (c) 1982,200 5, Oracle. all rights reserved. connect to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-ProductionWith the Partitioning, OLAP and Data Mining options SQL> alter system set event = '100 trace name context forever, level 10 'scope = spfile; the system has changed. Www.2cto.com SQL> startup force <-- the database is shut down abnormally. As a result, the preceding transaction has been started to roll back the ORACLE routine after the database is started. Total System Global Area 176160768 bytesFixed Size 1247900 bytesVariable Size 104858980 bytesDatabase Buffers 58720256 bytesRedo Buffers 11333632 bytes database loaded. The database has been opened. From the TRACE file of SMON, www.2cto.com can see the behavior of SMON: Dump file c: export _ smon_5604.trcMon Jan 21 19:25:36 2013 ORACLE V10.2.0.1.0-Production vsnsta = 0 vsnsql = 14 vsnxtr = 3 Oracle Database 10g Enterprise Edition Release 10.2.0.1.0-ProductionWith the Partitioning, OLAP and Data Mining optionsWindows XP Version V5.1 Service Pack 3CPU: 4-type 586, 2 Physical CoresProcess Affinit Y: 0x00000000Memory (Avail/Total): Ph: 1777 M/3240 M, Ph + PgF: 3242 M/5125 M, VA: 1729 M/2047 MInstance name: plsqldb Redo thread mounted by this instance: 0 <none> Oracle process number: 8 Windows thread id: 5604, image: ORACLE. EXE (SMON) *** service name :() 19:25:36. 437 *** session id: (120.1) 19:25:36. 437 **** 19:25:36. 437 SMON: system monitor started *** 19:25:36. 7 18 SMON: system monitor process posted *** 19:25:54. 593 SMON: system monitor process posted *** 19:25:54. 812 SMON: system monitor process posted *** 19:25:57. 765 SMON: system monitor process postedDead transaction 0x0009. 01f. 000002e5 recovered by 8 server (s) <---- SMON enabled 8 processes for transaction recovery. * ** 19:26:06. 078 SMON: Parallel transaction recovery tried *** 19:26:12. 546 Shrinking rbseg #0 <-- contract the temporary segment www.2cto.com *** 19:26:12. 546 Shrinking rbseg #1 *** 19:26:12. 562 Shrinking rbseg #2 *** 19:26:12. 562 Shrinking rbseg #3 *** 19:26:12. 578 Shrinking rbseg #4 *** 19:26:12. 578 Shrinking rbseg #5 *** 19:26:12. 593 Shrinking rbseg #6 *** 19:26:12. 609 Shrinking rbseg #7 *** 19:26:12. 625 Shrinking rbseg #8 *** 19:26:12. 625 Shrinking rbseg #9 *** 19:26:12. 625 Shrinking rbseg #10 *** 19:26:12. 640 SMON: system monitor process posted *** 19:26:12. 640 SMON: Posted too frequently, trans recovery disabled.