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fdbclient/StorageServerInterface.h

@@ -442,8 +442,9 @@ struct SplitMetricsRequest {
 struct ReadHotRangeWithMetrics {
 	KeyRangeRef keys;
 	// density refers to the ratio of bytes sent(because of the read) and bytes on disk.
-	// For example if key range [A, C) has byte size 100 bytes on disk and was read 100 times,
-	// density in this case equals to 100.
+	// For example if key range [A, B) and [B, C) respectively has byte size 100 bytes on disk.
+	// Key range [A,B) was read 30 times.
+	// The density for key range [A,C) is 30 * 100 / 200 = 15
 	double density;
 	// How many bytes of data was sent in a period of time because of read requests.
 	double readBandwidth;