Software Architect's Handbook

Service interface granularity

Making decisions about interface granularity can be very important in service-oriented design. Granularity can have a significant impact on performance and other concerns. Usually, a service interface contains more than one operation, and the operations of a service should be semantically related.

Fine-grained service operations offer greater flexibility to service consumers but lead to more network overhead, which could reduce performance. The more coarse-grained service operations we have, the less flexible they are, although they do reduce network overhead and could therefore improve performance.

Software architects should seek to find the right balance between the number of services and the number of operations ...