Advanced Customization > Services and Infrastructure Customization > Import Export Framework > How to Write Exp/Imp Handlers > How to Write a Class (Element) Import Handler > Multi Threading Considerations
  
Multi Threading Considerations
Starting in Windchill 10.2 M010, you can export and import Windchill package delivery files using multiple threads. Multiple threads provide one option that may be used to optimize performance. The use of multiple threads for the export of Windchill package delivery files is controlled using the wt.ixb.export.maxThreads property. The use of multiple threads for the import of Windchill received delivery files is controlled using the wt.ixb.import.maxThreads property.
Multi Thread Properties
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The import multithreading property only applies to import of a received delivery for importable packages.
Property
Description
wt.ixb.import.batchSize
Sets the batch size for a thread.
Batch size has lower impact on received delivery import performance. The property can be set to determine the number of objects in each import batch. By default, this property is set to 10000.
wt.ixb.import.maxThreads
Number of threads for import. The job list will be distributed over the number of threads you define.
Using multiple threads has the most significant impact on received delivery import performance. The threads share the same database connection, which can impact performance if the threshold is reached. The number of objects can also impact performance; the greater the number or objects, the greater the performance improvement when using multiple threads. In general, one thread will be sufficient for incremental package deliveries. An initial package delivery may benefit from multiple threads, particularly if the import time window is small. When importing CAD objects, this property must be set to 1. By default, this property is set to 1.
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The value of the wt.ixb.import.maxThreads property is used in conjunction with the wt.ixb.import.noOfParallelImportPaths property, which determines the number of transactions used for import.
• Single Transaction Scenario: If the wt.ixb.import.noOfParallelImportPaths property is set to 1, the value of the wt.ixb.import.maxThreads property is the total number of threads used for import.
• Multiple Transaction Scenario: If the value of the wt.ixb.import.noOfParallelImportPaths is set to more than 1, the value of the wt.ixb.import.maxThreads property is the number of threads used per import transaction.
wt.ixb.import.objPerThreadGuidance
Sets the number of objects included in each thread.
wt.ixb.export.maxThreads
Sets the maximum number of threads used for export. If there are fewer objects, the number of threads decreases accordingly. The recommended number is two.
wt.ixb.export.objPerThreadGuidance
Sets the number of objects included in each thread.
Related Documentation
For more information about this and other available properties that can affect Windchill package delivery file export performance, see Best Practices for Working with Packages. For more information about properties related to Windchill received delivery import performance, see Best Practices for Working with Received Deliveries.