@duration vs @expires vs "over window:time(x)

[Ivan Kostyuk]

@duration - an event persists in the working memory of the engine until its duration time has lapsed;

@expires - the time duration before an event expires in the working memory;

over window:time(x) - a sliding time window is a specified period of time during which events can be processed

https://docs.drools.org/7.63.0.Final/drools-docs/html_single/#drl-declarations-metadata-tags-ref_decision-engine

https://docs.drools.org/7.63.0.Final/drools-docs/html_single/#cep-sliding-windows-con_decision-engine

For @duration, I guess, the value is taken from an attribute. In what units?

Using the sliding window, it seems, makes it more efficient due to proper internal structure. Besides the structure, are all three give the same benefits?