Function dipstick::async

pub fn async<M, IC>(queue_size: usize, chain: IC) -> Chain<M> where
    M: Clone + Send + Sync + 'static,
    IC: Into<Chain<M>>, 

Cache metrics to prevent them from being re-defined on every use. Use of this should be transparent, this has no effect on the values. Stateful sinks (i.e. Aggregate) may naturally cache their definitions.