Appendix E - RAM Utilization for CBS on a 64-bit OS

CBS is a 32bit application. As a result it can only utilize up to 2Gb of RAM in a 32bit operating system. This is a limit set by the operating system. If the Large Address Aware flag is enabled, CBS will be able to address up to 4Gb of RAM in a 64bit operating system which support this option, provided that there is more than 4Gb of physical memory available. This will allow CBS to use up to 4Gb of RAM in order to handle larger data volumes under a 64bit operating systems.

From IFS Applications 7.5 Service Pack 5 onwards CBS Server/Client executable and related dll files comes with LARGE_ADDRESS_AWARE option enabled

How to Set LARGE_ADDRESS_AWARE flag

From IFS Applications 7.5 Service Pack 5 onwards the CBS Server executable and the belonging dll files will have the LARGE_ADDRESS_AWARE flag set. Therefore if you are using IFS Applications 7.5 Service Pack 5 or a later version this option is already enabled and no other changes are needed to address extra memory in a 64bit system.

System Requirements

In order to utilize the advantages of this setting and handle large volumes of data, underlying machine must provide sufficient resources and OS must also support it. Therefore following requirements must be met in order to address more than 2Gb of RAM.

• 64bit Operating System.
• Operating System must support more than 4Gb of physical memory.
• Sufficient physical memory installed. Ex: If CBS is expected to use 4Gb of RAM then there must be about 6Gb of total physical memory.

Note: If sufficient physical memory is not available OS may start using swap file space for CBS server/client reducing performance significantly.

Note: If CBS server is running in a 64bit environment in order to handle large data volumes, CBS clients that run against the same CBS server will also need to run in a 64bit machine with sufficient resources. This is because CBS clients load all the data that are there in CBS server, and as a result clients will need as much memory as CBS server is using.

Note: When an application has LARGE_ADDRESS_AWARE flag set, technically it is possible for it to use up to 3Gb of memory in a 32bit operating system that support 4-Gigabyte Tuning (4GT). But it is strongly discouraged to use CBS in a 32bit operating system with 4GT enabled. That can lead to various errors and communication failures as a result of operating system running low on memory.