> Second, the author is looking for a solution that can run in soft real time, so that it can be used for system monitoring. Histograms can absolutely be used

> Second, the author is looking for a solution that can run in soft real time, so that it can be used for system monitoring. Histograms can absolutely be used for alerting. We have done this at Circonus for ages: https://www.circonus.com/features/analytics/ https://www.circonus.com/features/analytics/ I wrote up the case of latency monitoring 6 weeks ago here: https://www.circonus.com/2018/08/30/latency-slos-done-right/ https://www.circonus.com/2018/08/30/latency-slos-done-right/