Amministrazione generale > Windchill ESI > Administering Windchill ESI in an SAP Environment > Administration Tasks > Configuring and Administering JMS Queues > Configuring JMS Queue Performance
  
Configuring JMS Queue Performance
Windchill ESI services offer three performance-related preferences that affect how they communicate with the JMS queues. Reasonable default values have been established for the preferences and these values are used during installation. However, depending on your environment, you may need to adjust these preferences to suit your particular needs.
The recommended approach is to modify the preferences incrementally and observe the performance effects. You can experiment with different values until you achieve the best overall performance.
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Large-scale changes can lead to performance degradation. Make small incremental changes and observe performance before making further changes.
The following lists the default settings for these preferences. Use the Preference Management utility to change any of these defaults.
Preference Name
Default
Description
JMS Queue Subscription Attempts Count
12
Defines the number of times the task helper should wait for the interval (specified by the preference Wait Time for JMS Queue Subscription) after a failed test to see if the Windchill Method Server is ready to process Windchill ESI RPCs.
Wait Time for JMS Queue Subscription
10000
Defines the amount of time, in milliseconds, the task helper should wait after a failed test to see if the Windchill Method Server is ready to process Windchill ESI RPCs.
Collection Size Multiplier
4
Defines the collection size intended to hold the result calculations of other new collections that some Windchill ESI java classes create. When the calculation is expected to create additional entries, the new collection is given an initial size using the following formula: new collection size = the original collection size multiplied by the value of this preference.