Multi-threading for data extraction

Note that Salesforce and RSA Archer is not supported for this functionality

When migrating data from a server you can increase the performance of the retrieval by configuring the Max Retrieval Threads option within the Advanced Execution Options for all forms, or within individual Form Mapping Options.

By default, this setting is set to 1 for single threaded retrieval of data but by increasing this, Precision Bridge will utilize several threads each concurrently extracting rows of data up to the number defined in the Max Retrieve Size.

While you can specify a possible maximum of 20 threads, you should take the following into account when defining this value:

• For a Service Now source, the number of nodes within your instance and the number of semaphores within these nodes
• The number of cores on your client machine running Precision Bridge
• Other integrations into your source instance
• Other instances of Precision Bridge that may be running concurrently.
• Possible licencing restrictions

If your source server is overloaded by the number of concurrent operations, a fatal error can occur during the migration. Users of the server for other purposes can also be impacted.

It is recommended that you increase the number of threads by a small amount and review the performance of your migration and also the impact on the source instance. Even increasing the Max Retrieval Threads to 2 or 3 can have a huge impact on the time required to perform the retrieval.

If your migration project includes forms with a small number of records to migrate (less than Max Retrieve Size), it is recommended that the Max Retrieval Threads is configured to 1 within the Form Mapping Options for these forms as multithreading may actually decrease performance.

Note that if an inclusion filter is used to retrieve all 'child' records for a set of 'parent' records from a Service Now source instance, each thread will concurrently process the fixed number of 'parent' records (50 for Service Now).