I found what seems to be a mapping API call on the swagger doc to turn on/off storage efficiency.
https://library.netapp.com/ecmdocs/ECMLP2876964/html/index.html#/storage/volume_modify
Would this API call cover the turn on/off part too ?
There are a bunch of efficiency settings available. If you scroll down to the body parameter (will show a black box with an example JSON value in it) and click on the "model" tab:
, you can read more about each of the fields:
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