redis-cli: fix latency result output

(Cleaned up a little by @mattsta)

Closes #1774

src/redis-cli.c

@@ -1850,11 +1850,15 @@ static void intrinsicLatencyMode(void) {
             printf("Max latency so far: %lld microseconds.\n", max_latency);
         }
 
+        double avg_us = (double)run_time/runs;
+        double avg_ns = avg_us * 10e3;
         if (force_cancel_loop || end > test_end) {
-            printf("\n%lld total runs (avg %lld microseconds per run).\n",
-                runs, run_time/runs);
-            printf("Worst run took %.02fx times the average.\n",
-                (double) max_latency / (run_time/runs));
+            printf("\n%lld total runs "
+                "(avg latency: "
+                "%.4f microseconds (%.2f nanoseconds) per run).\n",
+                runs, avg_us, avg_ns);
+            printf("Worst run took %.0fx longer than the average latency.\n",
+                max_latency / avg_us);
             exit(0);
         }
     }