ORA-00845: MEMORY_TARGET not Supported on This System-优快云博客

本文链接：https://blog.youkuaiyun.com/chncaesar/article/details/17318891

本文介绍了解决Oracle启动时遇到ORA-00845错误的方法。该错误通常是因为MEMORY_TARGET参数不被当前操作系统支持或者Linux系统中/dev/shm分区大小配置不当引起。通过调整系统的内存分配并确保/dev/shm至少等于SGA_MAX_SIZE的大小，可以有效解决此问题。

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ORA-00845:

MEMORY_TARGET not supported on this system

Cause: The MEMORY_TARGET parameter was not supported on this operating system or /dev/shm was not sized correctly on Linux.
Action: Refer to documentation for a list of supported operating systems. Or, size /dev/shm to be at least the SGA_MAX_SIZE on each Oracle instance running on the system.

Solution:

I'm using an Oracle Linux 6.4 64 bit with 4GB RAM on VirtualBox, and change Oracle's memory configuration
alter system set MEMORY_MAX_TARGET = 2048M scope=spfile;
Apparently, there's no enough memory for Oracle to startup. As by default, Oracle Linux uses 50% of total RAM as /dev/shm.
df -h | grep shm
tmpfs 2.0G 284K 2.0G 1% /dev/shm

Increasing RAM size and bounce Linux should solve the issue
df -h | grep shm
tmpfs 3.0G 112K 3.0G 1% /dev/shm

[oracle@odilab ~]$ sqlplus "/as sysdba"

SQL*Plus: Release 11.2.0.1.0 Production on Sun Nov 24 00:29:47 2013

Copyright (c) 1982, 2009, Oracle. All rights reserved.

Connected to an idle instance.

SQL< startup
ORACLE instance started.

Total System Global Area 2137886720 bytes
Fixed Size 2215064 bytes
Variable Size 1610613608 bytes
Database Buffers 520093696 bytes
Redo Buffers 4964352 bytes
Database mounted.
Database opened.