acceleratorCount

The number of the accelerator cards of this type exposed to this instance. Often restricted to one of 1, 2, 4, or 8.

The Cloud Dataproc API can return unintuitive error messages when using accelerators; even when you have defined an accelerator, Auto Zone Placement does not exclusively select zones that have that accelerator available. If you get a 400 error that the accelerator can't be found, this is a likely cause. Make sure you check accelerator availability by zone if you are trying to use accelerators in a given zone.