There's no point in plugging the same node into bump and displacement.

And it doesn't look like you have displacement turned on. The bump is only going to do the same as displacement without actually moving the vertices.

When trying to work out displacement, do that alone, and set the amount high so you can see it. Work out the desired pattern with the amount exaggerated, so you can see it. Then dial it back.

In this render, the donut on the right has a very high displacement amount - 5 times what I plan to use. I can see the pattern easily.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)