[Java] Automatically increase send interval to match the target messa…

…ge rate when calculating the batch size.

benchmarks-api/src/main/java/uk/co/real_logic/benchmarks/remote/LoadTestRig.java

@@ -175,8 +175,20 @@ long send(final int iterations, final int numberOfMessages)
         // The `sendIntervalNs` might be off if the division is not exact in which case more messages will be sent per
         // second than specified via `numberOfMessages`. However, this guarantees that the duration of the send
         // operation is bound by the number of iterations.
-        final long sendIntervalNs = Math.max(NANOS_PER_SECOND / numberOfMessages, configuration.messageSendDelayNs());
-        final int burstSize = (int)Math.ceil((double)numberOfMessages / (int)(NANOS_PER_SECOND / sendIntervalNs));
+        long sendIntervalNs = Math.max(NANOS_PER_SECOND / numberOfMessages, configuration.messageSendDelayNs());
+        int burstSize = numberOfMessages / (int)(NANOS_PER_SECOND / sendIntervalNs);
+        while (burstSize * (int)(NANOS_PER_SECOND / sendIntervalNs) < numberOfMessages)
+        {
+            sendIntervalNs *= 10;
+            if (sendIntervalNs > NANOS_PER_SECOND)
+            {
+                sendIntervalNs /= 10;
+                burstSize++;
+                break;
+            }
+            burstSize = numberOfMessages / (int)(NANOS_PER_SECOND / sendIntervalNs);
+        }
+
         final long totalNumberOfMessages = (long)iterations * numberOfMessages;
         final long startTimeNs = clock.nanoTime();
         final long stopTimeNs = startTimeNs + (iterations * NANOS_PER_SECOND);