Scalability of Clustered Installations

Clustering the database, the file system, web servers, and Sterling B2B Integrator can provide significant scalability while improving availability and reliability. Small clusters are fairly easy to implement and can provide a better solution than using a larger server.

Scalability refers to the ability of Sterling B2B Integrator to handle changes in volume through the solution of technical and operational issues.

You should pay careful attention to database performance in a clustered environment. With two nodes, generally twice as many business processes are executing at the same time, so the database and all of the other components must be scaled to match. Adding a node (or even upgrading the application server platform to have more processors) increases the load across the environment.

The overall performance in a clustered environment is limited by four factors:
  • The granularity of the work being done
  • The arrangement of the adapters
  • The performance of the database engine
  • Interaction between processes (for example, locks and synchronization)
You can improve the scalability of a business process by doing the following:
  • Changing the amount of data processed in each business process.
  • Changing the amount of work done in each step.
  • Changing the division of labor between business processes.
  • Avoiding locking or synchronization between processes.

However, some business processes will not scale well. One example of this is a process in which a single row in the database must be updated by each instance of the business process. This constraint will force the processes to run sequentially, at least while they are updating the row.