General Memory and Disk Space Requirements

This section contains the general, minimum memory and disk space requirements for Oracle Fusion Middleware, including Oracle Fusion Middleware Infrastructure.

The following topics are covered:

• General Memory Requirements
  
• Temporary Disk Space Requirements
  

General Memory Requirements

The following sections provide general information about how to determine the amount of memory required to run the Oracle Fusion Middleware products you have purchased:

• Minimum Memory Requirement for Installing Oracle Fusion Middleware
  
• Using a Formula to Determine Memory Requirements for a Specific Deployment
  
• Example: Determining Memory Requirements for a Development Environment
  
• Example: Determining Memory Requirements for a Production Environment
  
• Considering the Impact of Open File and Process Limits on Memory Requirements
  

Minimum Memory Requirement for Installing Oracle Fusion Middleware

Unless otherwise noted, Table 2-1 lists the general minimum memory requirements for installing Oracle Fusion Middleware products.

Note:

For the purposes of this document, memory requirements fall into two categories: physical memory (the amount of physical RAM installed on host) and the minimum available memory, which includes swap space in addition to the physical memory.

The memory requirements listed here are minimum requirements. The actual required memory will vary, depending upon the number of Managed Servers and the number of Oracle Fusion Middleware products you configure in the domains on each host. For some guidelines about determining the amount of memory required for a specific deployment, see Using a Formula to Determine Memory Requirements for a Specific Deployment.

If you plan to install and configure a database instance on the same server, you should add at least an additional 2 GB of physical and 2 GB of available memory. For more information about memory requirements for the database, see the documentation for your database software version.

Table 2-1 Memory Requirements for Installing Oracle Fusion Middleware

Operating System	Minimum Physical Memory Required	Minimum Available Memory Required
Linux	4 GB	8 GB
UNIX	4 GB	8 GB
Windows	4 GB	8 GB

Using a Formula to Determine Memory Requirements for a Specific Deployment

Oracle Fusion Middleware installations vary widely in terms of how the Oracle WebLogic Server domains that support them are configured. For example, in some highly available production environments, you might have several Managed Servers running on each host. On the other hand, a single Administration Server, configured in a supported compact domain configuration is adequate for some development purposes.

To estimate the amount of required memory required to run Oracle Fusion Middleware 12c in a particular deployment configuration, you can consider the amount of memory required by the operating system and other software, and then add a set amount of memory that will be required for each Java Virtual Machine (JVM) that you plan to configure on the host. Each Managed Server configured in a domain represents a single JVM instance.

Note:

It is recommended that for the performance of a well-scaled production environments, the total Java heap memory allocations for all the Managed Servers per host add up to no more than 50% of the total physical memory on the host. If larger JVM heap sizes are required, or more managed servers are needed, physical memory should be increased accordingly.

In general, you can use the following formula as a general guideline to predict the minimum available memory requirements for Oracle Fusion Middleware:

    3 GB of available memory for the operating system and other software
 +  3 GB of available memory for each Managed Server
-----------------------------------------------------
    Total required available memory

It is important to note that this is a general guideline and the actual memory required for the operating system or a specific Managed Server can vary widely, depending on the resources and services targeted to the host or to the Managed Server.

Example: Determining Memory Requirements for a Development Environment

When determining memory required for a development environment, consider the type of domain you are using to test your applications.

If you are using the integrated Oracle WebLogic Server domain, which you run directly from Oracle JDeveloper, see Oracle JDeveloper Requirements.

If you are configuring a compact domain for your development system, you can use the general memory formula in Using a Formula to Determine Memory Requirements for a Specific Deployment as a guideline to determine the initial required memory requirements.

In the compact domain scenario, all resources are targeted to the Administration server, so you need enough memory to support the operating system and one Administration Server:

   3 GB for the operating system and other software
 + 3 GB for the Administration Server
-------------------------------------
   6 GB of available memory

Example: Determining Memory Requirements for a Production Environment

In a production environment, Oracle recommends as a best practice that you target products and services to specific Managed Servers and clusters, based on the resources required by the products and services.

For example, in a typical enterprise deployment of Oracle SOA Suite, you target Oracle Web Services Manager (OWSM) to one cluster and Oracle SOA Suite to another cluster. This can result in a domain with multiple Managed Servers on each host. As you add additional managed clusters, the memory requirements increase.

For example, if you are planning to configure a Oracle WebLogic Server domain with an Administration Server and two Managed Servers, then you could use the following formula to determine the minimum required available memory:

   3 GB for the operating system and other software
   3 GB for the Admin Server 
 + 6 GB for the two Managed Servers
--------------------------------------
  12 GB

Considering the Impact of Open File and Process Limits on Memory Requirements

When determining the memory requirements for a production environment, you should also take into account other operating system settings, including the number of file descriptors (open files) allowed per process and the number of processes required for each product or service that is targeted to a Managed Server.

For information about the recommended minimum open file and process limits for Oracle Fusion Middleware, see Setting the Open File Limit and Number of Processes Settings on UNIX Systems.

For an example of the minimum amount of memory, file descriptors, and processes required for an enterprise deployment in a production environment, see Typical Memory, File Descriptors, and Processes Required for an Oracle SOA Suite Enterprise Deployment in the Enterprise Deployment Guide for Oracle SOA Suite.

Temporary Disk Space Requirements

The installation program uses a temporary directory into which it extracts the files that are needed to install the software on the target system. During the installation process, your temporary directory must contain sufficient space to accommodate the compressed Java Run-time Environment (JRE) bundled with the installation program and an uncompressed copy of the JRE that is expanded into the temporary directory. The extracted files are deleted from the temporary directory after the installation process. The files in the temporary directory require approximately 2.5 times the space that is ultimately required for the installation.

By default, the installation program uses the following temporary directories:

• Windows platforms—directory referenced by the TMP system variable

• UNIX platforms—system-dependent temporary directory

  Note:

  If you do not have enough temporary space to run the installation program, you are prompted to specify an alternate directory or exit the installation program.

To make sure that you have adequate temporary space, you may want to allocate an alternate directory for this purpose by doing one of the following (depending on your operating system:

• On Windows operating systems, set the TMP system variable to a directory of your choice.

• Run the installation program from the command line and include the -Djava.io.tmpdir=tmpdirpath option, replacing tmpdirpath with the full path of the directory you want to designate as a temporary storage area for the installation program.

  For example, to set up the temporary directory while running the Oracle Fusion Middleware Infrastructure installer for Windows, run the following command:

  java -Djava.io.tmpdir=C:\Temp -jar fmw_infra_121200.jar
  

  Similarly, to set up the temporary directory while running a platform-specific installer, such as the Oracle HTTP Server installer on a Linux system, run the following command:

  ./ohs_linux64.bin -J-Djava.io.tmpdir=/scratch/<temp dir>