1 files changed, 113 insertions, 0 deletions
diff --git a/src/main/java/org/openecomp/sparky/synchronizer/TransactionRateController.java b/src/main/java/org/openecomp/sparky/synchronizer/TransactionRateController.java
new file mode 100644
index 0000000..8cc3409
--- /dev/null
+++ b/src/main/java/org/openecomp/sparky/synchronizer/TransactionRateController.java
@@ -0,0 +1,113 @@
+/**
+ * ============LICENSE_START===================================================
+ * SPARKY (AAI UI service)
+ * ============================================================================
+ * Copyright © 2017 AT&T Intellectual Property.
+ * Copyright © 2017 Amdocs
+ * All rights reserved.
+ * ============================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=====================================================
+ *
+ * ECOMP and OpenECOMP are trademarks
+ * and service marks of AT&T Intellectual Property.
+ */
+
+package org.openecomp.sparky.synchronizer;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.openecomp.sparky.analytics.AveragingRingBuffer;
+import org.openecomp.sparky.synchronizer.config.TaskProcessorConfig;
+
+/**
+ * TODO: Fill in description.
+ * 
+ * @author davea.
+ */
+public class TransactionRateController {
+
+  private AveragingRingBuffer responseTimeTracker;
+  private double msPerTransaction;
+  private int numThreads;
+  private TaskProcessorConfig config;
+  private long startTimeInMs;
+  private AtomicInteger numTransactions;
+
+  /**
+   * Instantiates a new transaction rate controller.
+   *
+   * @param config the config
+   */
+  public TransactionRateController(TaskProcessorConfig config) {
+
+    this.config = config;
+    this.responseTimeTracker = new AveragingRingBuffer(
+        config.getNumSamplesPerThreadForRunningAverage() * config.getMaxConcurrentWorkers());
+    this.msPerTransaction = 1000 / config.getTargetTps();
+    this.numThreads = config.getMaxConcurrentWorkers();
+    this.startTimeInMs = System.currentTimeMillis();
+    this.numTransactions = new AtomicInteger(0);
+  }
+
+  /**
+   * Track response time.
+   *
+   * @param responseTimeInMs the response time in ms
+   */
+  public void trackResponseTime(long responseTimeInMs) {
+    this.numTransactions.incrementAndGet();
+    responseTimeTracker.addSample(responseTimeInMs);
+  }
+
+  public long getFixedDelayInMs() {
+
+    /*
+     * The math here is pretty simple:
+     * 
+     * 1. Target TPS is 10. Then the msPerTxn = 1000/10 = 100ms
+     * 
+     * 2. If the calculated avgResponseTime = 40 ms, then the proposed delay is 60ms per thread.
+     * 
+     * 3. If the calculated avgResponseTime = 200ms, then the proposed delay is -100 ms, which is
+     * not possible, we can't speed it up, so we don't propose any further delay.
+     */
+
+    double proposedDelay = 0;
+
+    if (config.isTransactionRateControllerEnabled()) {
+      proposedDelay = ((msPerTransaction - responseTimeTracker.getAvg()) * this.numThreads);
+
+      if (proposedDelay > 0) {
+        return (long) (proposedDelay);
+      }
+    }
+
+    return (long) proposedDelay;
+  }
+
+  public long getAvg() {
+    return responseTimeTracker.getAvg();
+  }
+
+  public double getCurrentTps() {
+    if (numTransactions.get() > 0) {
+      double timeDelta = System.currentTimeMillis() - startTimeInMs;
+      double numTxns = numTransactions.get();
+      return (numTxns / timeDelta) * 1000.0;
+    }
+
+    return 0.0;
+  }
+
+}