进程体系结构-白红宇

进程体系结构

阅读量：5868 次

发布时间：2019-06-19

本文共 8427 字，大约阅读时间需要 28 分钟。

一：进程简介

应用程序或者Oracle数据库实用程序

Oracle数据库代码

1：多进程Oracle 数据库代码

2：进程类型

实例恢复：SMON

清理进程：PMON

重做缓冲区写入磁盘：dbwn

---查看数据库状态SYS@orcl>  status  v$instance;STATUS---------------从上得知：此时数据库是打开open状态：查看此时数据库的后台进程信息SYS@orcl> ho  ps -ef |grep ora_oracle   11999     1  0 May09 ?        00:00:05 ora_pmon_orcloracle   12001     1  0 May09 ?        00:00:18 ora_psp0_orcloracle   12003     1  0 May09 ?        00:00:29 ora_vktm_orcloracle   12007     1  0 May09 ?        00:00:01 ora_gen0_orcloracle   12009     1  0 May09 ?        00:00:01 ora_diag_orcloracle   12011     1  0 May09 ?        00:00:02 ora_dbrm_orcloracle   12013     1  0 May09 ?        00:00:10 ora_dia0_orcloracle   12015     1  0 May09 ?        00:00:01 ora_mman_orcloracle   12017     1  0 May09 ?        00:00:19 ora_dbw0_orcloracle   12019     1  0 May09 ?        00:00:28 ora_lgwr_orcloracle   12021     1  0 May09 ?        00:00:26 ora_ckpt_orcloracle   12023     1  0 May09 ?        00:01:10 ora_smon_orcloracle   12025     1  0 May09 ?        00:00:01 ora_reco_orcloracle   12027     1  0 May09 ?        00:00:20 ora_mmon_orcloracle   12029     1  0 May09 ?        00:01:48 ora_mmnl_orcloracle   12031     1  0 May09 ?        00:00:01 ora_d000_orcloracle   12033     1  0 May09 ?        00:00:02 ora_s000_orcloracle   12062     1  0 May09 ?        00:00:09 ora_arc0_orcloracle   12064     1  0 May09 ?        00:00:10 ora_arc1_orcloracle   12066     1  0 May09 ?        00:00:01 ora_arc2_orcloracle   12070     1  0 May09 ?        00:00:14 ora_arc3_orcloracle   12072     1  0 May09 ?        00:00:01 ora_qmnc_orcloracle   12088     1  0 May09 ?        00:00:17 ora_cjq0_orcloracle   12092     1  0 May09 ?        00:00:01 ora_q000_orcloracle   12126     1  0 May09 ?        00:00:01 ora_smco_orcloracle   25238     1  0 15:56 ?        00:00:00 ora_q002_orcloracle   28073     1  0 22:00 ?        00:00:00 ora_vkrm_orcloracle   28839     1  0 23:41 ?        00:00:00 ora_w000_orcloracle   28853 28836  0 23:42 pts/2    00:00:00 /bin/bash -c ps -ef |grep ora_oracle   28855 28853  0 23:42 pts/2    00:00:00 grep ora_SYS@orcl>

---删除后台进程 smon ；SYS@orcl> ho  -9 12023/bin/bash: line 0: : (12023) -  such process---再来查看数据库状态SYS@orcl>  status  v$instance; status  v$instance*ERROR  line 1:ORA-03135:  lost contactProcess ID: 28837 ID: 200 Serial number: 4305---从查询结果来看：数据库的o'r'c'l实例已经不存在了，所以其数据库状态 也就不存在；SYS@orcl>

---此时：oracle的所有后台进程全部终止SYS@orcl> ho  ps -ef |grep ora_oracle   28885 28836  0 23:48 pts/2    00:00:00 /bin/bash -c ps -ef |grep ora_oracle   28887 28885  0 23:48 pts/2    00:00:00 grep ora_SYS@orcl>

SYS@orcl> Disconnected  Oracle  11g Enterprise Edition Release 11.2.0.3.0 - Production the Partitioning, OLAP, Data Mining   Application Testing options[oracle@localhost ~]$  sqlplus /  sysdba;*Plus: Release 11.2.0.3.0 Production  Mon May 14 23:49:37 2018Copyright (c) 1982, 2011, Oracle.   rights reserved.Connected  an idle instance.---退出再登陆后；发现此时是空闲实例SYS@orcl>

----当数据库实例不能运行或者阻塞状态时，可以直接 kill -9  smon后台进程；然后再重新启动数据库：SYS@orcl> Disconnected  Oracle  11g Enterprise Edition Release 11.2.0.3.0 - Production the Partitioning, OLAP, Data Mining   Application Testing options[oracle@localhost ~]$ rlwrap sqlplus /  sysdba;*Plus: Release 11.2.0.3.0 Production  Mon May 14 23:49:37 2018Copyright (c) 1982, 2011, Oracle.   rights reserved.Connected  an idle instance.SYS@orcl>  startupORACLE instance started.Total System  Area  523108352 bytesFixed                   1346052 bytesVariable              394266108 bytes Buffers          121634816 bytesRedo Buffers                5861376 bytes mounted. opened.SYS@orcl> ho  ps -ef |grep ora_oracle   28970     1  0 23:53 ?        00:00:00 ora_pmon_orcloracle   28972     1  0 23:53 ?        00:00:00 ora_psp0_orcloracle   28974     1  0 23:53 ?        00:00:00 ora_vktm_orcloracle   28978     1  0 23:53 ?        00:00:00 ora_gen0_orcloracle   28980     1  0 23:53 ?        00:00:00 ora_diag_orcloracle   28982     1  0 23:53 ?        00:00:00 ora_dbrm_orcloracle   28984     1  0 23:53 ?        00:00:00 ora_dia0_orcloracle   28986     1  3 23:53 ?        00:00:00 ora_mman_orcloracle   28988     1  0 23:53 ?        00:00:00 ora_dbw0_orcloracle   28990     1  0 23:53 ?        00:00:00 ora_lgwr_orcloracle   28992     1  0 23:53 ?        00:00:00 ora_ckpt_orcloracle   28994     1  0 23:53 ?        00:00:00 ora_smon_orcloracle   28996     1  0 23:53 ?        00:00:00 ora_reco_orcloracle   28998     1  2 23:53 ?        00:00:00 ora_mmon_orcloracle   29000     1  0 23:53 ?        00:00:00 ora_mmnl_orcloracle   29002     1  0 23:53 ?        00:00:00 ora_d000_orcloracle   29004     1  0 23:53 ?        00:00:00 ora_s000_orcloracle   29033     1  0 23:53 ?        00:00:00 ora_p000_orcloracle   29035     1  0 23:53 ?        00:00:00 ora_p001_orcloracle   29037     1  0 23:53 ?        00:00:00 ora_p002_orcloracle   29039     1  0 23:53 ?        00:00:00 ora_arc0_orcloracle   29041     1  9 23:53 ?        00:00:00 ora_arc1_orcloracle   29043     1 12 23:53 ?        00:00:01 ora_arc2_orcloracle   29045     1  9 23:53 ?        00:00:00 ora_arc3_orcloracle   29051     1  0 23:53 ?        00:00:00 ora_qmnc_orcloracle   29067     1  2 23:53 ?        00:00:00 ora_cjq0_orcloracle   29069     1  0 23:54 ?        00:00:00 ora_vkrm_orcloracle   29071     1 16 23:54 ?        00:00:00 ora_j000_orcloracle   29073     1  3 23:54 ?        00:00:00 ora_j001_orcloracle   29075     1  4 23:54 ?        00:00:00 ora_j002_orcloracle   29077     1  0 23:54 ?        00:00:00 ora_j003_orcloracle   29078 28891  0 23:54 pts/2    00:00:00 /bin/bash -c ps -ef |grep ora_oracle   29080 29078  0 23:54 pts/2    00:00:00 grep ora_SYS@orcl>

二：客户端进程描述

1：客户端和服务器进程

oracle 进程必须是在 oracle服务器上产生

2：连接和会话

三：服务器进程概述

1：专用服务器进程

2：共享服务器进程

四：后台进程概述

查看后台进程

SYS@orcl>  linesize 3000;SYS@orcl>  pname    pname      pname;PNAME-----ARC0ARC1ARC2ARC3CJQ0CKPTD000DBRMDBW0DIA0DIAGPNAME-----GEN0J000J001LGWRMMANMMNLMMONPMONPSP0Q000Q001PNAME-----QMNCRECOS000SMCOSMONVKTMW00029  selected.SYS@orcl>

SYS@orcl> oracle    3497     1  0 09:49 ?        00:00:00 ora_w000_orcloracle    3635     1  0 10:00 ?        00:00:00 ora_j000_orcloracle    3637     1  0 10:00 ?        00:00:00 ora_j001_orcloracle    3638 28891  0 10:01 pts/2    00:00:00 /bin/bash -c ps -ef |grep ora_oracle    3640  3638  0 10:01 pts/2    00:00:00 grep ora_oracle   28970     1  0 May14 ?        00:00:00 ora_pmon_orcloracle   28972     1  0 May14 ?        00:00:01 ora_psp0_orcloracle   28974     1  0 May14 ?        00:00:01 ora_vktm_orcloracle   28978     1  0 May14 ?        00:00:00 ora_gen0_orcloracle   28980     1  0 May14 ?        00:00:00 ora_diag_orcloracle   28982     1  0 May14 ?        00:00:00 ora_dbrm_orcloracle   28984     1  0 May14 ?        00:00:00 ora_dia0_orcloracle   28986     1  0 May14 ?        00:00:00 ora_mman_orcloracle   28988     1  0 May14 ?        00:00:01 ora_dbw0_orcloracle   28990     1  0 May14 ?        00:00:01 ora_lgwr_orcloracle   28992     1  0 May14 ?        00:00:02 ora_ckpt_orcloracle   28994     1  0 May14 ?        00:00:00 ora_smon_orcloracle   28996     1  0 May14 ?        00:00:00 ora_reco_orcloracle   28998     1  0 May14 ?        00:00:01 ora_mmon_orcloracle   29000     1  0 May14 ?        00:00:03 ora_mmnl_orcloracle   29002     1  0 May14 ?        00:00:00 ora_d000_orcloracle   29004     1  0 May14 ?        00:00:00 ora_s000_orcloracle   29039     1  0 May14 ?        00:00:00 ora_arc0_orcloracle   29041     1  9 May14 ?        00:55:49 ora_arc1_orcloracle   29043     1  9 May14 ?        00:55:37 ora_arc2_orcloracle   29045     1  9 May14 ?        00:55:33 ora_arc3_orcloracle   29051     1  0 May14 ?        00:00:00 ora_qmnc_orcloracle   29067     1  0 May14 ?        00:00:00 ora_cjq0_orcloracle   29082     1  0 May14 ?        00:00:00 ora_q000_orcloracle   29084     1  0 May14 ?        00:00:00 ora_q001_orcloracle   29130     1  0 May14 ?        00:00:00 ora_smco_orclSYS@orcl>

1：强制性后台进程

               进程监视器进程 PMON

即：如果 PMOM进程出现问题，则数据库的网络连接可能链接不了

               系统监视器进程 SMON

表空间：居多使用的都是本地管理方式

               数据库写入器进程DBwn

DBWn: n 表示数字：从0 开始 1，2，3，4，5……….

增量检查点

               日志写入器进程 LGWR

commit ；命令执行的操作：此时只是把缓冲区的数据写入到练级重做日志文件。此时数据还未写入到数据文件。

3秒钟开始执行

先执行 LGWR 然后再执行 DBwn 。即：当缓冲区的脏数据写入到练级重做日志文件后，才开始将数据缓冲区的数据写入到数据库文件中。

               LGWR与提交

当 ckpt开始工作的时候，调用 DBWn开始工作，把缓冲区的数据写入到数据文件中，并从日志文件中获取SCN号来更新控制文件和数据文件头部的SCN号。

                恢复器进程 RECO