Designing processes - EMC Community Network

Performance and Scalability
technology on system performance. In most cases, clients are willing to reconsider a feature that
negatively impacts system performance.
Mandatory search attributes
When designing a search panel, identify the mandatory fields so the user must always enter them to
improve performance. Most attributes that are drop-downs or check boxes qualify for this case. Once
you make them mandatory, create a composite index on these combined attributes. This ensures all
search queries will at least use this index, instead of open-ended searches, to improve performance.
Task lists
Task lists are one of the most frequently used views in TaskSpace. The best performing task lists limit
the number of SDTs and process variables that appear within the task list. Each additional SDT and
process variable results in a new query to the database. When several concurrent users are working
on the system, these queries add up. As a practical matter, you can consolidate one or more process
variables into a single SDT. For example, a task list containing nine process variables takes 10 seconds
to 15 seconds to populate the window. The same task list built with one SDT containing nine attributes
takes only 3 seconds to 5 seconds. The difference is that the first task list issued nine requests to the
database while the second task list issued only one request. (The best way to understand this behavior
is to take a single click trace of the transaction).
Consider the number of filters that you create in a task list because each filter impacts system
performance.
You can further improve task list performance by disabling full-text indexing if it is not being used.
Refer to Disabling full-text indexing, page 103 for more information.
Preconditions
Be careful when using preconditions in a TaskSpace application because they inject row-by-row
processing into the response time. If there are ten tasks in a task list and there is a precondition
defined for the object type, then the precondition fires ten times. Although preconditions provide
rich functionality, they can negatively affect system performance. For example, a task queue with
preconditions took 8 seconds to 10 seconds to render. Without the preconditions, the same task list
rendered in 3 seconds.
It is recommended that you take a baseline timing of a task or search form before you add
preconditions. After you establish the baseline, the incremental performance cost of a feature can be
assessed. Associate a response time or resource cost for each feature request. Then it is possible to
calculate the cost and benefit of each feature. Calculate a cost, even if a feature is mandatory. Discuss
feature costs together with performance and scalability with the client.
To optimize custom action preconditions for datagrid rendering, define scope values for action
definitions that use the precondition.
Avoid permission checking in precondition classes, since the system will do object full fetches for each
data row. If your precondition must do permission checking, consider using lazy evaluation by adding
the oneexecutiononly=’true’ attribute in the tag.
EMC Documentum xCelerated Composition Platform Version 1.6 Best Practices Guide 99