Clarify doc comment

tokio/src/runtime/builder.rs

@@ -1245,18 +1245,19 @@ impl Builder {
         ///     .unwrap();
         /// ```
         ///
-        /// Configure a `LogHistogram` with similar behavior to [`HistogramScale::Log`]
+        /// When migrating from the legacy histogram ([`HistogramScale::Log`]) and wanting
+        /// to match the previous behavior, use `precision_exact(0)`. This creates a histogram
+        /// where each bucket is twice the size of the previous bucket.
         /// ```rust
-        ///
         /// use std::time::Duration;
         /// use tokio::runtime::{HistogramConfiguration, LogHistogram};
         /// let rt = tokio::runtime::Builder::new_current_thread()
         ///     .enable_all()
         ///     .enable_metrics_poll_time_histogram()
         ///     .metrics_poll_time_histogram_configuration(HistogramConfiguration::log(
         ///         LogHistogram::builder()
-        ///             .max_value(Duration::from_millis(4))
         ///             .min_value(Duration::from_micros(20))
+        ///             .max_value(Duration::from_millis(4))
         ///             // Set `precision_exact` to `0` to match `HistogramScale::Log`
         ///             .precision_exact(0)
         ///             .max_buckets(10)