This is documentation for Mathematica 7, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.1)


is an option for Manipulate, Dynamic and related functions which specifies whether or not to evaluate their contents synchronously.
  • If a dynamic object that needs to be updated has the setting SynchronousUpdating->True, the front end will wait for the necessary evaluation to be completed before going on to any other tasks.
  • If a dynamic object has the setting SynchronousUpdating->False, the front end will queue up its evaluation, and allow it to be performed asynchronously.
  • For dynamic objects that take a long time to update, the updating may time out unless the objects have SynchronousUpdating->False.
  • SynchronousUpdating->Automatic specifies that synchronous updating should be used when controls in an object such as Manipulate are active, and asynchronous updating should be used otherwise.
By default Manipulate will time out if the contents take more than 5 seconds to evaluate:
By disabling SynchronousUpdating, the evaluation will not time out:
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