When you plan a new WebSphere Event Broker domain,
you must first have considered your resource naming conventions, the design
of the WebSphere MQ infrastructure, and any performance
issues. The following topics describe these considerations:
When you are designing a broker domain consider the following
elements.
Brokers: The number of brokers that you need in your domain
depends on the following factors:
Performance: What is the required message throughput? (Refer
to Optimizing message flow throughput). What is the size of the
messages that are being processed? Larger messages take longer to process.
A small number of brokers handling many messages might impact the broker domain's
performance. Refer to Considering performance in the domain.
Do you need to isolate applications from each other? You might
want to separate applications that serve different functions, for example
personnel and finance.
User Name Server: Consider the following
if you have a User Name Server in your broker domain:
Performance: If you have a large number of brokers in your broker
domain, the requests that they send the User Name Server can
be handled more quickly if there is more than one User Name Server.
More than one User Name Server might also be beneficial
(in terms of network traffic) if your broker domain is complex.
Resilience: Although no standby mechanism is provided by WebSphere Event Broker, you might want to be able to redirect
requests to a second User Name Server if a system
error occurs on the system of your first User Name Server.
Configuration
Manager: This acts as an
interface between the configuration repository and the set of brokers in the
domain and the workbench. It uses WebSphere
MQ messages
to communicate with the brokers, and thus a large number of brokers in a broker
domain (if poorly designed) can cause congestion at the Configuration
Manager.
To solve this, consider dividing the brokers into more than one domain where
related brokers are kept together. You can then establish connections with
each domain (refer to Creating a domain connection).