ORA-00845 MEMORY_TARGET not supported on this system 的解決

oracle11g數據庫在執行dbca或者調整sga後重啓oracle的時候可能會出現ORA-00845 MEMORY_TARGET not supported on this system 錯誤。
究其緣由就是Linux系統的shm的大小比SGA設置的小，形成的，距離來講，SGA設置4G，而shm可能只有1G

網上提供兩種解決辦法：
0一、調整sga的大小，這個明顯不是咱們所但願的
0二、調整shm的大小，這樣相對簡單，具體操做以下
vi /etc/fstab
修改以下行的設置
tmpfs /dev/shm tmpfs defaults 0 0
改爲
tmpfs /dev/shm tmpfs defaults,size=6G 0 0
保存退出
從新mount下shm使其生效
mount -o remount /dev/shm
經過df能夠查看下，沒有問題就能夠繼續安裝數據庫或者啓動數據庫了！

 

 

說明：服務器上有兩個不一樣數據庫實例，啓動一個實例的時候沒問題。在啓動第二個INSTANCE的時候報ORA-00845錯誤。該測試服務器僅8G內存。   tmpfs     默認是4G            4.0G  1.6G  2.4G  40% /dev/shm.  兩個實例的使用內存應該超過了4G，因此安裝網上這篇文章進行修改tmpfs，問題解決了。  可是新問題tmpfs 大小的限制如何肯定呢？觀察一下內存使用在說吧

 

 

[oracle@BJRMANTS ~]$ su - root
Password:
[root@BJRMANTS ~]# vi /etc/fstab
[root@BJRMANTS ~]# df -g
df: invalid option -- 'g'
Try `df --help' for more information.
[root@BJRMANTS ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2              20G  5.8G   13G  31% /
tmpfs                 4.0G  1.6G  2.4G  40% /dev/shm
/dev/sda1             485M   51M  409M  12% /boot
/dev/sda6             197G  160G   28G  86% /orabak
/dev/sda8              20G  6.2G   13G  34% /oracle
/dev/sda5             690G  549G  106G  84% /oradata
/dev/sda7             187G   75G  104G  42% /oralog
[root@BJRMANTS ~]# mount -o remount /dev/shm
[root@BJRMANTS ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2              20G  5.8G   13G  31% /
tmpfs                 6.0G  1.6G  4.5G  26% /dev/shm
/dev/sda1             485M   51M  409M  12% /boot
/dev/sda6             197G  160G   28G  86% /orabak
/dev/sda8              20G  6.2G   13G  34% /oracle
/dev/sda5             690G  549G  106G  84% /oradata
/dev/sda7             187G   75G  104G  42% /oralog
[root@BJRMANTS ~]#

 

[oracle@BJRMANTS ~]$ export ORACLE_SID=oelncbi
[oracle@BJRMANTS ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.3.0 Production on Wed Dec 5 10:48:51 2012

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup;
ORA-00845: MEMORY_TARGET not supported on this system
SQL> exit
Disconnected
[oracle@BJRMANTS ~]$ export ORACLE_SID=oeldzdz
[oracle@BJRMANTS ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.3.0 Production on Wed Dec 5 10:49:33 2012

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> shutdown abort;
ORACLE instance shut down.
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@BJRMANTS ~]$ export ORACLE_SID=oelncbi
[oracle@BJRMANTS ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.3.0 Production on Wed Dec 5 10:49:51 2012

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup;
ORACLE instance started.

Total System Global Area  814227456 bytes
Fixed Size      2232760 bytes
Variable Size    452988488 bytes
Database Buffers   352321536 bytes
Redo Buffers      6684672 bytes
Database mounted.
Database opened.
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@BJRMANTS ~]$ export ORACLE_SID=oeldzdz
[oracle@BJRMANTS ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.3.0 Production on Wed Dec 5 10:54:15 2012

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup;
ORACLE instance started.

Total System Global Area 2805977088 bytes Fixed Size      2231672 bytes Variable Size    603980424 bytes Database Buffers  2181038080 bytes Redo Buffers     18726912 bytes Database mounted. Database opened. SQL>