Oracle體繫結構及備份（十三） bg-pmon

一 什麼是PMON進程

The process monitor performs processrecovery when a user process fails. PMON is responsible for cleaning up thecache and freeing resources that the process was using. PMON also checks on thedispatcher processes (described later in this table) and server processes andrestarts them if they have failed.

PMON，進程監控進程（動態註冊監聽器）

作用：

清除失敗的進 程

復原事務

釋放鎖

釋放其他資源

重啟死掉的Dispatchers

二 操作樣本

oracle@localhost 案頭]$  ps -ef | grep ora_ | grep pmon  oracle    2889     1  0 17:01 ?        00:00:00 ora_pmon_orcl  [oracle@localhost 案頭]$ kill -9 2889  [oracle@localhost 案頭]$  ps -ef | grep ora_ | grep pmon  [oracle@localhost 案頭]$  ps -ef | grep ora_  oracle    2950  2597  0 17:05 pts/0    00:00:00 grep ora_  [oracle@localhost 案頭]$  ps -ef | grep ora_ | grep pmon  [oracle@localhost 案頭]$ sqlplus / as sysdba;        SQL*Plus: Release 10.2.0.1.0 - Production on Tue Jun 4 17:05:59 2013        Copyright (c) 1982, 2005, Oracle.  All rights reserved.        Connected to an idle instance.        SQL> conn scott/tiger;  ERROR:  ORA-01034: ORACLE not available  ORA-27101: shared memory realm does not exist  Linux Error: 2: No such file or directory              Warning: You are no longer connected to ORACLE.  SQL> conn / as sysdba;  Connected to an idle instance.  SQL> exit;  Disconnected  [oracle@localhost 案頭]$  ps -ef | grep ora_  oracle    2963  2597  0 17:06 pts/0    00:00:00 grep ora_  [oracle@localhost 案頭]$ startup  bash: startup: command not found  [oracle@localhost 案頭]$ sqlplus / as sysdba;        SQL*Plus: Release 10.2.0.1.0 - Production on Tue Jun 4 17:07:01 2013        Copyright (c) 1982, 2005, Oracle.  All rights reserved.        Connected to an idle instance.        SQL> startup  ORACLE instance started.        Total System Global Area  838860800 bytes  Fixed Size          1222192 bytes  Variable Size         775948752 bytes  Database Buffers       58720256 bytes  Redo Buffers            2969600 bytes  Database mounted.  Database opened.        SQL> conn scott/tiger;  Connected.  SQL> exit;  Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production  With the Partitioning, OLAP and Data Mining options  [oracle@localhost 案頭]$  ps -ef | grep ora_  oracle    2968     1  0 17:07 ?        00:00:00 ora_pmon_orcl  oracle    2970     1  0 17:07 ?        00:00:00 ora_psp0_orcl  oracle    2972     1  0 17:07 ?        00:00:00 ora_mman_orcl  oracle    2974     1  0 17:07 ?        00:00:00 ora_dbw0_orcl  oracle    2976     1  0 17:07 ?        00:00:00 ora_lgwr_orcl  oracle    2978     1  0 17:07 ?        00:00:00 ora_ckpt_orcl  oracle    2980     1  0 17:07 ?        00:00:00 ora_smon_orcl  oracle    2982     1  0 17:07 ?        00:00:00 ora_reco_orcl  oracle    2984     1  0 17:07 ?        00:00:00 ora_cjq0_orcl  oracle    2986     1  1 17:07 ?        00:00:00 ora_mmon_orcl  oracle    2988     1  0 17:07 ?        00:00:00 ora_mmnl_orcl  oracle    2990     1  0 17:07 ?        00:00:00 ora_d000_orcl  oracle    2992     1  0 17:07 ?        00:00:00 ora_s000_orcl  oracle    2996     1  0 17:07 ?        00:00:00 ora_qmnc_orcl  oracle    2998     1  2 17:07 ?        00:00:00 ora_j000_orcl  oracle    3004     1  0 17:07 ?        00:00:00 ora_q000_orcl  oracle    3006     1  0 17:07 ?        00:00:00 ora_q001_orcl  oracle    3009  2597  0 17:07 pts/0    00:00:00 grep ora_  [oracle@localhost 案頭]$  ps -ef | grep ora_ | grep pmon  oracle    2968     1  0 17:07 ?        00:00:00 ora_pmon_orcl

三 總結

1. PMON，進 程監控進程，動態註冊監聽器。

2.作用：清除失敗的進程、復原事務、釋放鎖、釋放其他資源、重啟 死掉的Dispatchers。

3.Linux下仍然採用ps命令查看。