Especially on initially adding to your chart. Often requires toggling show/hide indicator to get it to complete script execution within the time limit. YMMV!
From TASC Sept 2016 this is Ehler's Autocorrelation periodogram. A means of determining the dominant cycle ("ideal" indicator length / dynamic length).
As an example it's applied here to or . Lower indicator segment displays the autocorrelation spectrum and the computed dominant cycle. Upper segment is / .
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.