SOA_011：如何评估ESB容量 （摘录+整理）

为了评估ESB所需要的容量，需要考虑以下方面：
■ The number of message instances
■ The path through the ESB for each message
■ Throughput of ESB messages, including:
– Peak throughput per hour
– Sustained throughput per hour
■ Load of ESB messages, including:
– Peak load start time and duration
– Sustained load duration
■ Resource sizing
– The number and sizes of documents, or payloads, passed between the ESB
processes and the web services they use
– The average response time for synchronous process during normal load
– Average response time for synchronous process during peak load
■ Fault-tolerance – is High Availability required, or is cold failover acceptable?
In addition to business requirements, the needs of the ESB processes that will be used
need to be considered and estimated. These needs include:
■ Payload size
Select the system resource capacity to accommodate the anticipated payloads plus
reserve capacity. This is particularly an issue for Java-based application server
components. For example, a 50 MB XML document in memory is large and
therefore a challenge to process unless system resources are unusually generous.
For efficiency, the best practice is to break up large payloads into smaller pieces.
■ Data transformations performed
■ End points and integration points
■ Number of Web services used and how often the ESB process invokes them
■ Type of Web service invocations, synchronous or asynchronous
■ Anticipated response times for both synchronous callbacks