Regardless of the value of the test option, the configuration still must be validated before it is applied to the running datastore, that’s why you see lots of get callback invocations. There is no configuration option that would turn this validation off.
You can affect that however: if the data model is under your control, you can tweak the constraints that are causing this, up to the point that you remove them completely and implement the validation only in your database (note that this is somewhat extreme solution). If you are not the owner of the YANG modules, you can still do a lot here either using YANG annotations or, in the worst case, deviations.
Again - I suggest you first try to identify what constraint or constraints are causing this behavior.