Grafana is mainly built around time series databases that have good roll ups and are usually quite fast. Graphite queries usually only take 50-150ms (except some rare cases). This is changing a bit with newer slower time series databases that don&#x27;t have good roll ups or are generally slow.<p>The main problem with prefetching or doing delta fetches is that some queries depend on the whole time range to execute (like moving average, integral, derivate).