Caching and Deferred Execution 

Also software applications follow the famous 80:20 rule. They spent 80% of the execution time in 20% of their operations. In other words: Only a small part of the code-base is relevant for the performance of a software system. Portal applications spent most of the time for I/O operations, for example, accessing a database or communicating with an external system.

Therefore I/O-intensive operations have to be used with care, especially with the following APIs:

PCD/Portal Content Directory

UME/User Management Engine

KM/Knowledge Management

JCo/Java Connector for SAP backend system

These APIs involve a lot of database processing and that leads to long execution times. Therefore, they should be avoided and/or consolidated whenever possible. Use the following strategies to reduce I/O operations:

·        Delay expensive operations and avoid preloading.

·        Keep information in memory that is likely to be queried again.

·        Consolidate multiple operations to one (for example, SQL statements).

·        Avoid file I/O in requests.