Introducing services and load balancing

Unlike other messaging-oriented middlewares that operate with queues, Tuxedo operates with another abstraction level on top of that – a service. A service may be backed by one or more queues and multiple services may use the same queue. The mapping between service names and queues is stored in the Bulletin Board. The client uses this mapping information and chooses the appropriate queue and tells the kernel which queue to use for a request, as shown in the following diagram. No mapping is required for the response queue as the client tells the server exactly which queue to use for the response:

Figure 3.5 – A service

There are a couple of ways in which the service abstraction over queues can be used, so let's explore them in detail.

Exploring the MSSQ configuration

MSSQ stands for Multiple Servers Single Queue. In modern terminology, we would say that a queue has multiple consumers. Instead of...