Designing processes - EMC Community Network

Chapter 8
Performance and Scalability
This chapter discusses the following:
• General approach to performance
• System configuration guidelines
• Factors that affect performance and scalability
• Recommended application server settings
• Recommended Content Server settings
• Recommended database server settings
• Tuning and troubleshooting performance problems
General approach to performance
This section discusses general performance theory. Performance analysis treats a large number of
different metrics, such as response time, throughput, efficiency, and capacity. The two that are the most
important to process-based applications are response time and throughput.
• Response time measures the amount of time you must wait to receive any response to a request;
for example, running a series of automated activities may incur a response time of one second
between each one.
• Throughput measures the number of transactions the system can process per unit of time; for
example, a system may be able to handle only 100 TaskSpace searches per minute.
As you design the application, you should:
• Not go deep. The reason for the recommendation to not go deep is that every layer of database
tables generates additional joins that impact performance. You should keep your inheritance
hierarchy as flat as you can.
• Tune for the highest-yield queries. Yield is the number of times a query is executed multiplied by
the execution time of the query. By anticipating the yield and tuning it for the highest-yield query,
your performance does not degrade unacceptably for that use case. To achieve this you may need to
de-normalize, pulling attributes into one or two physical tables.
In general, the recommended approach to performance testing is to carry out two classes of tests:
• Single user profiling — In single-user profiling you run unit tests, such as collecting Documentum
Class Library (DMCL)/DFC traces.
• Load testing — In load testing you are looking for bottlenecks and capacity issues.
EMC Documentum xCelerated Composition Platform Version 1.6 Best Practices Guide 95