Wolfram Language & System 11.0 (2016)|Legacy Documentation

This is documentation for an earlier version of the Wolfram Language.View current documentation (Version 11.2)

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is a unique ID number assigned to each running parallel kernel.


  • The value of $KernelID for the master kernel is 0.
  • The value of $KernelID for each subkernel is a distinct positive integer, assigned when the kernel is launched.
  • Values of $KernelID are unique but not necessarily contiguous.
Introduced in 2008