setup 11 (1)

rlwrap-0.37

11g 新增加 memory_target  (同時控制sga和pga)----》但sga_max_size可以等於memory_target
 
 sga_target + pga_aggregate_target= memory_target--->sga_max_size

mount tmpfs /dev/shm -t tmpfs -o size=6000m

tmpfs                   /dev/shm                tmpfs   size=6000m      0 0

本次安裝基於的環境

 

DELL R710 (Intel Quad Core X5650 Xeon 2.66 GHz * 22 GB * 4146 GB * 6RAID10+RAID5))

Linux 5.0 U3 64Bit


一、 安裝前的準備工作

 

1硬體需求

1.1記憶體相關檢查

  建議安裝前仔細閱讀官方的Installtion Guide,瞭解自己的硬體架構是否符合安裝需求。

  我們使用Linux 5.0 Update 3 64bit,按照官方建議

  On Linux X86-64:

  RAM: 至少4G(我們的實體記憶體為8G)

 

[root@PLSFCWEBDB ~]# grep MemTotal  /proc/meminfo

MemTotal:      8168284 kB

 

  SWAP: 實體記憶體在4~8G的,SWAP為實體記憶體的2倍;

       實體記憶體在8~32G的,SWAP為實體記憶體的1.5倍;

           實體記憶體大於32G的,SWAP為32G

      (我們的SWAP設為與實體記憶體相等)

 

[root@PLSFCWEBDB ~]# grep SwapTotal  /proc/meminfo

SwapTotal:     8385888 kB

  

查看當前可用記憶體和SWAP使用狀況

 

[root@PLSFCWEBDB ~]# free

             total       used       free     shared    buffers     cached

Mem:       8168284    2230380    5937904          0     246324    1731276

-/+ buffers/cache:     252780    7915504

Swap:      8385888          0    8385888

 

ORACLE 資料庫從11g 版本開始,引入了一個自動記憶體管理(Automatic Memory Management)特性,該特性需要更多的共用記憶體(/dev/shm),因此如果決定應用該特性的話, 必須要確保共用記憶體大於ORACLE 中初始化參數MEMORY_MAX_TARGET 和MEMORY_TARGET(特別提示,這兩個參數即自動記憶體管理特性對應的初始化參數)的值。

如果在初始化參數中設置了MEMORY_MAX_TARGET 和MEMORY_TARGET 兩參數為非0 值,並且不符合系統共用記憶體,則ORACLE 資料庫啟動時,就會觸發ORA-00845:MEMORY_TARGET not supported on this system 錯誤。

 

ORACLE官方文檔中的原話為:

Automatic Memory Management

Starting with Oracle Database 11g, the Automatic Memory Management feature requires more shared memory (/dev/shm)and file descriptors. The size of the shared memory should be at least the greater of MEMORY_MAX_TARGET and MEMORY_TARGET

for each Oracle instance on the computer. If MEMORY_MAX_TARGET or MEMORY_TARGET is set to a non zero value, and an incorrect size is assigned to the shared memory, it will result in an ORA-00845 error at startup. On Linux systems, if the operating system /dev/shm mount size is too small for the Oracle system global area (SGA) and program global area (PGA), even then it will result in an ORA-00845 error.

The number of file descriptors for each Oracle instance should be at least 512*PROCESSES. Also, the limit of descriptors for each process should be at least 512.

If file descriptors are not sized correctly, you will notice ORA-27123 from various Oracle processes and potentially Linux Error EMFILE (Too many open files) errors in non-Oracle processes.

To determine the amount of shared memory available, enter the following command:

 

# df -h /dev/shm/

 

[root@PLSFCWEBDB ~]# df -h /dev/shm/

Filesystem            Size  Used Avail Use% Mounted on

tmpfs                 3.9G     0  3.9G   0% /dev/shm

 

默認的,Linux /dev/shm的大小為物理內存的50%。 

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转载于:http://blog.itpub.net/25072296/viewspace-697391/

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