How to configure physical memory in oracle

Oracle is a very popular relational database management system that is widely used in enterprises. For first-time users of Oracle, installation and configuration is one of the processes that must be mastered. During the installation of Oracle, the size of physical memory directly affects the performance and reliability of the database. Therefore, in order to ensure the stable operation of Oracle services, you must understand how to configure physical memory.

1. How to check physical memory?

Before installing Oracle, you need to check how much physical memory your system has. In the operating system, you can check the physical memory through the following command:

$ free -m

or

$ cat /proc/meminfo

Both of the above two methods can obtain the physical memory information of the system. Among them, the free -m command will display a summary of memory usage, as shown below:

             total       used       free     shared    buffers     cached
Mem:          7983       3697       4285          0         60       1766
-/+ buffers/cache:       1870       6113
Swap:         7993          0       7993

In the above information, total represents the size of physical memory in units of Megabyte (MB).

2. The physical memory size required by Oracle services

Before installing Oracle, you need to understand the physical memory size required by different versions of Oracle services. The following is the physical memory size required for Oracle 11g releases:

• Oracle Standard Edition One and Standard Edition: 1GB
• Oracle Standard Edition Two: 2GB
• Oracle Enterprise Edition :2GB

For 64-bit operating systems, the Oracle service requires an additional 500MB of physical memory.

In addition, when choosing the installation type, you also need to consider the size of physical memory. If you choose the typical installation mode, the required physical memory size will be larger. Therefore, before installing Oracle, the physical memory of the system needs to be evaluated.

3. How to configure physical memory?

After evaluating the system's physical memory and Oracle service needs, the next step is to configure the physical memory. First, you need to ensure that the size of the swap partition (swap) in the system is large enough. Oracle's installation program automatically checks and sets the appropriate swap partition size. Generally speaking, the size of the swap partition should be twice the physical memory.

After the swap partition size has been set, you need to allocate appropriate physical memory for the Oracle service. For 32-bit operating systems, the maximum limit of user space is 4GB, so the physical memory size of the Oracle service cannot exceed 4GB. However, in actual operation, some space needs to be reserved for the operating system and other applications. Therefore, the physical memory size of the Oracle service can be set between 1.5GB and 2GB.

For 64-bit operating systems, Oracle services can use more physical memory. However, you also need to reserve some space for the operating system and other applications. Therefore, the physical memory size of the Oracle service can be set between 3GB and 4GB.

4. The impact of physical memory size

The size of physical memory will affect the performance and reliability of Oracle. If the system's physical memory is too small, the performance of Oracle services will be severely affected. At this time, Oracle may issue an out-of-memory error message, causing the service to become unavailable. Therefore, when installing Oracle, you need to ensure that the physical memory of the system is large enough to ensure the normal operation of Oracle services.

When installing Oracle services, the size of physical memory is a very important parameter. If you accidentally set the wrong physical memory size, it may cause unstable performance of the entire system. Therefore, before installation, it is necessary to evaluate the physical memory of the system and set the physical memory size according to actual needs to ensure the best performance and reliability of Oracle services.

The above is the detailed content of How to configure physical memory in oracle. For more information, please follow other related articles on the PHP Chinese website!