From f09166cb5a3d1df958bf2686617c153e4e228b8f Mon Sep 17 00:00:00 2001
From: Nikola Koevski <nikola.koevski@camunda.com>
Date: Wed, 29 Apr 2020 15:49:35 +0200
Subject: [PATCH] feat(engine): add new pricing model metrics (#791)

- executed decision instances (dmn tables and literal expressions)
- root process instances (i.e. instances not started by call activity)
- refactors involved tests from JUnit 3 to 4

related to CAM-11186
---
 .../delegate/DmnDecisionEvaluationEvent.java  |   5 +
 .../impl/DefaultDmnDecisionContext.java       |   1 +
 .../DmnDecisionEvaluationEventImpl.java       |  14 ++
 .../metrics/DefaultEngineMetricCollector.java |  15 ++
 .../DmnEngineMetricCollectorWrapper.java      |  10 +
 .../engine/spi/DmnEngineMetricCollector.java  |  12 ++
 .../cfg/ProcessEngineConfigurationImpl.java   |   3 +
 .../MetricsDecisionEvaluationListener.java    |   9 +-
 .../parser/MetricsBpmnParseListener.java      |  20 +-
 .../parser/MetricsExecutionListener.java      |  17 +-
 .../bpm/engine/management/Metrics.java        |   6 +
 .../api/mgmt/metrics/AbstractMetricsTest.java |  45 ++++-
 .../ActivityInstanceCountMetricsTest.java     |   8 +-
 .../api/mgmt/metrics/DecisionMetricsTest.java | 175 ++++++++++++++++++
 .../ExecutedDecisionElementsMetricsTest.java  |  80 --------
 .../mgmt/metrics/JobExecutorMetricsTest.java  |  37 ++--
 .../api/mgmt/metrics/MetricsDisabledTest.java |  42 ++++-
 .../test/api/mgmt/metrics/MetricsTest.java    |  49 ++---
 .../RootProcessInstanceMetricsTest.java       | 145 +++++++++++++++
 .../db/entitymanager/PurgeDatabaseTest.java   |   2 +-
 20 files changed, 560 insertions(+), 135 deletions(-)
 create mode 100644 engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/DecisionMetricsTest.java
 delete mode 100644 engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ExecutedDecisionElementsMetricsTest.java
 create mode 100644 engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/RootProcessInstanceMetricsTest.java

diff --git a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/delegate/DmnDecisionEvaluationEvent.java b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/delegate/DmnDecisionEvaluationEvent.java
index b7aa7e5a566..d61dcdf021d 100644
--- a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/delegate/DmnDecisionEvaluationEvent.java
+++ b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/delegate/DmnDecisionEvaluationEvent.java
@@ -33,6 +33,11 @@ public interface DmnDecisionEvaluationEvent {
    */
   Collection<DmnDecisionLogicEvaluationEvent> getRequiredDecisionResults();
 
+  /**
+   * @return the number of executed decision instances during the evaluation
+   */
+  long getExecutedDecisionInstances();
+
   /**
    * @return the number of executed decision elements during the evaluation
    */
diff --git a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/DefaultDmnDecisionContext.java b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/DefaultDmnDecisionContext.java
index 145e029fac0..db95007d5ce 100644
--- a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/DefaultDmnDecisionContext.java
+++ b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/DefaultDmnDecisionContext.java
@@ -174,6 +174,7 @@ protected void generateDecisionEvaluationEvent(List<DmnDecisionLogicEvaluationEv
     }
 
     decisionEvaluationEvent.setDecisionResult(rootEvaluatedEvent);
+    decisionEvaluationEvent.setExecutedDecisionInstances(evaluatedEvents.size());
     decisionEvaluationEvent.setExecutedDecisionElements(executedDecisionElements);
 
     evaluatedEvents.remove(rootEvaluatedEvent);
diff --git a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/delegate/DmnDecisionEvaluationEventImpl.java b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/delegate/DmnDecisionEvaluationEventImpl.java
index d13c53ccfc1..c3ec157d6b1 100644
--- a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/delegate/DmnDecisionEvaluationEventImpl.java
+++ b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/delegate/DmnDecisionEvaluationEventImpl.java
@@ -27,8 +27,10 @@ public class DmnDecisionEvaluationEventImpl implements DmnDecisionEvaluationEven
 
   protected DmnDecisionLogicEvaluationEvent decisionResult;
   protected Collection<DmnDecisionLogicEvaluationEvent> requiredDecisionResults = new ArrayList<DmnDecisionLogicEvaluationEvent>();
+  protected long executedDecisionInstances;
   protected long executedDecisionElements;
 
+  @Override
   public DmnDecisionLogicEvaluationEvent getDecisionResult() {
     return decisionResult;
   }
@@ -37,6 +39,7 @@ public void setDecisionResult(DmnDecisionLogicEvaluationEvent decisionResult) {
     this.decisionResult = decisionResult;
   }
 
+  @Override
   public Collection<DmnDecisionLogicEvaluationEvent> getRequiredDecisionResults() {
     return requiredDecisionResults;
   }
@@ -45,6 +48,16 @@ public void setRequiredDecisionResults(Collection<DmnDecisionLogicEvaluationEven
     this.requiredDecisionResults = requiredDecisionResults;
   }
 
+  @Override
+  public long getExecutedDecisionInstances() {
+    return executedDecisionInstances;
+  }
+
+  public void setExecutedDecisionInstances(long executedDecisionInstances) {
+    this.executedDecisionInstances = executedDecisionInstances;
+  }
+
+  @Override
   public long getExecutedDecisionElements() {
     return executedDecisionElements;
   }
@@ -61,6 +74,7 @@ public String toString() {
       ", name="+ dmnDecision.getName() +
       ", decisionLogic=" + dmnDecision.getDecisionLogic() +
       ", requiredDecisionResults=" + requiredDecisionResults +
+      ", executedDecisionInstances=" + executedDecisionInstances +
       ", executedDecisionElements=" + executedDecisionElements +
       '}';
   }
diff --git a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DefaultEngineMetricCollector.java b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DefaultEngineMetricCollector.java
index 9a838c47182..93b458f043d 100644
--- a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DefaultEngineMetricCollector.java
+++ b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DefaultEngineMetricCollector.java
@@ -25,6 +25,7 @@
 
 public class DefaultEngineMetricCollector implements DmnEngineMetricCollector, DmnDecisionEvaluationListener {
 
+  protected AtomicLong executedDecisionInstances = new AtomicLong();
   protected AtomicLong executedDecisionElements = new AtomicLong();
 
   public void notify(DmnDecisionTableEvaluationEvent evaluationEvent) {
@@ -32,14 +33,28 @@ public void notify(DmnDecisionTableEvaluationEvent evaluationEvent) {
   }
 
   public void notify(DmnDecisionEvaluationEvent evaluationEvent) {
+    long executedDecisionInstances = evaluationEvent.getExecutedDecisionInstances();
     long executedDecisionElements = evaluationEvent.getExecutedDecisionElements();
+    this.executedDecisionInstances.getAndAdd(executedDecisionInstances);
     this.executedDecisionElements.getAndAdd(executedDecisionElements);
   }
 
+  @Override
+  public long getExecutedDecisionInstances() {
+    return executedDecisionInstances.get();
+  }
+
+  @Override
   public long getExecutedDecisionElements() {
     return executedDecisionElements.get();
   }
 
+  @Override
+  public long clearExecutedDecisionInstances() {
+    return executedDecisionInstances.getAndSet(0);
+  }
+
+  @Override
   public long clearExecutedDecisionElements() {
     return executedDecisionElements.getAndSet(0);
   }
diff --git a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DmnEngineMetricCollectorWrapper.java b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DmnEngineMetricCollectorWrapper.java
index bb53d053f97..f6b3735c6c3 100644
--- a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DmnEngineMetricCollectorWrapper.java
+++ b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/impl/metrics/DmnEngineMetricCollectorWrapper.java
@@ -51,11 +51,21 @@ protected void notifyCollector(DmnDecisionLogicEvaluationEvent evaluationEvent)
     // ignore other evaluation events since the collector is implemented as decision table evaluation listener
   }
 
+  @Override
+  public long getExecutedDecisionInstances() {
+    return collector.getExecutedDecisionInstances();
+  }
+
   @Override
   public long getExecutedDecisionElements() {
     return collector.getExecutedDecisionElements();
   }
 
+  @Override
+  public long clearExecutedDecisionInstances() {
+    return collector.clearExecutedDecisionInstances();
+  }
+
   @Override
   public long clearExecutedDecisionElements() {
     return collector.clearExecutedDecisionElements();
diff --git a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/spi/DmnEngineMetricCollector.java b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/spi/DmnEngineMetricCollector.java
index 622efbfe501..16d1f51e444 100644
--- a/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/spi/DmnEngineMetricCollector.java
+++ b/engine-dmn/engine/src/main/java/org/camunda/bpm/dmn/engine/spi/DmnEngineMetricCollector.java
@@ -24,6 +24,11 @@
  */
 public interface DmnEngineMetricCollector extends DmnDecisionTableEvaluationListener {
 
+  /**
+   * @return the number of executed decision instances since creation of this engine
+   */
+  long getExecutedDecisionInstances();
+
   /**
    * @return the number of executed decision elements since creation of this engine
    */
@@ -36,4 +41,11 @@ public interface DmnEngineMetricCollector extends DmnDecisionTableEvaluationList
    */
   long clearExecutedDecisionElements();
 
+  /**
+   * Resets the executed decision instances to 0.
+   *
+   * @return the number of executed decision elements before resetting.
+   */
+  long clearExecutedDecisionInstances();
+
 }
diff --git a/engine/src/main/java/org/camunda/bpm/engine/impl/cfg/ProcessEngineConfigurationImpl.java b/engine/src/main/java/org/camunda/bpm/engine/impl/cfg/ProcessEngineConfigurationImpl.java
index 38eaa75d1ad..98b6f80f84a 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/impl/cfg/ProcessEngineConfigurationImpl.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/impl/cfg/ProcessEngineConfigurationImpl.java
@@ -2173,6 +2173,9 @@ protected void initDefaultMetrics(MetricsRegistry metricsRegistry) {
     metricsRegistry.createMeter(Metrics.JOB_LOCKED_EXCLUSIVE);
     metricsRegistry.createMeter(Metrics.JOB_EXECUTION_REJECTED);
 
+    metricsRegistry.createMeter(Metrics.ROOT_PROCESS_INSTANCE_START);
+
+    metricsRegistry.createMeter(Metrics.EXECUTED_DECISION_INSTANCES);
     metricsRegistry.createMeter(Metrics.EXECUTED_DECISION_ELEMENTS);
   }
 
diff --git a/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/dmn/MetricsDecisionEvaluationListener.java b/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/dmn/MetricsDecisionEvaluationListener.java
index 889a3b69b76..346f8f3a7a3 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/dmn/MetricsDecisionEvaluationListener.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/dmn/MetricsDecisionEvaluationListener.java
@@ -20,6 +20,7 @@
 import org.camunda.bpm.dmn.engine.delegate.DmnDecisionEvaluationListener;
 import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
 import org.camunda.bpm.engine.impl.context.Context;
+import org.camunda.bpm.engine.impl.metrics.MetricsRegistry;
 import org.camunda.bpm.engine.management.Metrics;
 
 public class MetricsDecisionEvaluationListener implements DmnDecisionEvaluationListener {
@@ -28,9 +29,11 @@ public void notify(DmnDecisionEvaluationEvent evaluationEvent) {
     ProcessEngineConfigurationImpl processEngineConfiguration = Context.getProcessEngineConfiguration();
 
     if (processEngineConfiguration != null && processEngineConfiguration.isMetricsEnabled()) {
-      processEngineConfiguration
-        .getMetricsRegistry()
-        .markOccurrence(Metrics.EXECUTED_DECISION_ELEMENTS, evaluationEvent.getExecutedDecisionElements());
+      MetricsRegistry metricsRegistry = processEngineConfiguration.getMetricsRegistry();
+      metricsRegistry.markOccurrence(Metrics.EXECUTED_DECISION_INSTANCES,
+                                     evaluationEvent.getExecutedDecisionInstances());
+      metricsRegistry.markOccurrence(Metrics.EXECUTED_DECISION_ELEMENTS,
+                                     evaluationEvent.getExecutedDecisionElements());
     }
   }
 
diff --git a/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsBpmnParseListener.java b/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsBpmnParseListener.java
index c254176b47f..538da431b0f 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsBpmnParseListener.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsBpmnParseListener.java
@@ -18,10 +18,13 @@
 
 import org.camunda.bpm.engine.delegate.ExecutionListener;
 import org.camunda.bpm.engine.impl.bpmn.parser.AbstractBpmnParseListener;
+import org.camunda.bpm.engine.impl.persistence.entity.ExecutionEntity;
+import org.camunda.bpm.engine.impl.persistence.entity.ProcessDefinitionEntity;
 import org.camunda.bpm.engine.impl.pvm.process.ActivityImpl;
 import org.camunda.bpm.engine.impl.pvm.process.ScopeImpl;
 import org.camunda.bpm.engine.impl.util.xml.Element;
 import org.camunda.bpm.engine.management.Metrics;
+import org.camunda.bpm.engine.runtime.Execution;
 
 /**
  * @author Daniel Meyer
@@ -29,14 +32,27 @@
  */
 public class MetricsBpmnParseListener extends AbstractBpmnParseListener {
 
-  public static MetricsExecutionListener ACTIVITY_INSTANCE_START_COUNTER = new MetricsExecutionListener(Metrics.ACTIVTY_INSTANCE_START);
-  public static MetricsExecutionListener ACTIVITY_INSTANCE_END_COUNTER = new MetricsExecutionListener(Metrics.ACTIVTY_INSTANCE_END);
+  public static MetricsExecutionListener ROOT_PROCESS_INSTANCE_START_COUNTER =
+      new MetricsExecutionListener(Metrics.ROOT_PROCESS_INSTANCE_START,
+                                   delegateExecution -> (delegateExecution.getId().equals(
+                                           ((ExecutionEntity) delegateExecution)
+                                               .getRootProcessInstanceId())));
+  public static MetricsExecutionListener ACTIVITY_INSTANCE_START_COUNTER =
+      new MetricsExecutionListener(Metrics.ACTIVTY_INSTANCE_START);
+  public static MetricsExecutionListener ACTIVITY_INSTANCE_END_COUNTER =
+      new MetricsExecutionListener(Metrics.ACTIVTY_INSTANCE_END);
 
   protected void addListeners(ActivityImpl activity) {
     activity.addBuiltInListener(ExecutionListener.EVENTNAME_START, ACTIVITY_INSTANCE_START_COUNTER);
     activity.addBuiltInListener(ExecutionListener.EVENTNAME_END, ACTIVITY_INSTANCE_END_COUNTER);
   }
 
+  @Override
+  public void parseProcess(Element processElement, ProcessDefinitionEntity processDefinition) {
+    processDefinition.addBuiltInListener(ExecutionListener.EVENTNAME_START,
+                                         ROOT_PROCESS_INSTANCE_START_COUNTER);
+  }
+
   public void parseStartEvent(Element startEventElement, ScopeImpl scope, ActivityImpl activity) {
     addListeners(activity);
   }
diff --git a/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsExecutionListener.java b/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsExecutionListener.java
index eafb69f01a0..e5d48bb0ce9 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsExecutionListener.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/impl/metrics/parser/MetricsExecutionListener.java
@@ -16,6 +16,8 @@
  */
 package org.camunda.bpm.engine.impl.metrics.parser;
 
+import java.util.function.Function;
+
 import org.camunda.bpm.engine.delegate.DelegateExecution;
 import org.camunda.bpm.engine.delegate.ExecutionListener;
 import org.camunda.bpm.engine.impl.context.Context;
@@ -27,15 +29,24 @@
 public class MetricsExecutionListener implements ExecutionListener {
 
   protected String metricsName;
+  protected Function<DelegateExecution, Boolean> condition;
 
   public MetricsExecutionListener(String metricsName) {
+    this(metricsName, delegateExecution -> true);
+  }
+
+  public MetricsExecutionListener(String metricsName,
+                                  Function<DelegateExecution, Boolean> condition) {
     this.metricsName = metricsName;
+    this.condition = condition;
   }
 
   public void notify(DelegateExecution execution) throws Exception {
-    Context.getProcessEngineConfiguration()
-      .getMetricsRegistry()
-      .markOccurrence(metricsName);
+    if (condition.apply(execution)) {
+      Context.getProcessEngineConfiguration()
+          .getMetricsRegistry()
+          .markOccurrence(metricsName);
+    }
   }
 
 }
diff --git a/engine/src/main/java/org/camunda/bpm/engine/management/Metrics.java b/engine/src/main/java/org/camunda/bpm/engine/management/Metrics.java
index 73310ef8017..050242e8148 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/management/Metrics.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/management/Metrics.java
@@ -55,9 +55,15 @@ public class Metrics {
    */
   public final static String JOB_LOCKED_EXCLUSIVE = "job-locked-exclusive";
 
+  /**
+   * Number of executed Root Process Instance executions.
+   */
+  public final static String ROOT_PROCESS_INSTANCE_START = "root-process-instance-start";
+
   /**
    * Number of executed decision elements in the DMN engine.
    */
+  public final static String EXECUTED_DECISION_INSTANCES = "executed-decision-instances";
   public final static String EXECUTED_DECISION_ELEMENTS = "executed-decision-elements";
 
   /**
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/AbstractMetricsTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/AbstractMetricsTest.java
index c28d0929eed..4ea4a18853f 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/AbstractMetricsTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/AbstractMetricsTest.java
@@ -18,20 +18,57 @@
 
 import java.util.Collection;
 
+import org.camunda.bpm.engine.CaseService;
+import org.camunda.bpm.engine.HistoryService;
+import org.camunda.bpm.engine.ManagementService;
+import org.camunda.bpm.engine.RepositoryService;
+import org.camunda.bpm.engine.RuntimeService;
+import org.camunda.bpm.engine.TaskService;
+import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
 import org.camunda.bpm.engine.impl.metrics.Meter;
-import org.camunda.bpm.engine.impl.test.PluggableProcessEngineTestCase;
+import org.camunda.bpm.engine.test.ProcessEngineRule;
+import org.camunda.bpm.engine.test.util.ProcessEngineTestRule;
+import org.camunda.bpm.engine.test.util.ProvidedProcessEngineRule;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.rules.RuleChain;
 
 /**
  * @author Thorben Lindhauer
  *
  */
-public abstract class AbstractMetricsTest extends PluggableProcessEngineTestCase {
+public abstract class AbstractMetricsTest {
+
+  protected final ProcessEngineRule engineRule = new ProvidedProcessEngineRule();
+  protected final ProcessEngineTestRule testRule = new ProcessEngineTestRule(engineRule);
+
+  @Rule
+  public RuleChain ruleChain = RuleChain.outerRule(engineRule).around(testRule);
+
+  protected ProcessEngineConfigurationImpl processEngineConfiguration;
+  protected RuntimeService runtimeService;
+  protected TaskService taskService;
+  protected CaseService caseService;
+  protected HistoryService historyService;
+  protected RepositoryService repositoryService;
+  protected ManagementService managementService;
+
+  @Before
+  public void initializeServices() throws Exception {
+    processEngineConfiguration = engineRule.getProcessEngineConfiguration();
+    runtimeService = engineRule.getRuntimeService();
+    taskService = engineRule.getTaskService();
+    caseService = engineRule.getCaseService();
+    historyService = engineRule.getHistoryService();
+    repositoryService = engineRule.getRepositoryService();
+    managementService = engineRule.getManagementService();
 
-  protected void setUp() throws Exception {
     clearMetrics();
   }
 
-  protected void tearDown() throws Exception {
+  @After
+  public void cleanUpMetrics() throws Exception {
     clearMetrics();
   }
 
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ActivityInstanceCountMetricsTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ActivityInstanceCountMetricsTest.java
index 1f39c8c971e..c5b35e95b7f 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ActivityInstanceCountMetricsTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ActivityInstanceCountMetricsTest.java
@@ -16,6 +16,8 @@
  */
 package org.camunda.bpm.engine.test.api.mgmt.metrics;
 
+import static org.junit.Assert.assertEquals;
+
 import java.util.List;
 
 import org.camunda.bpm.engine.history.HistoricTaskInstance;
@@ -24,6 +26,7 @@
 import org.camunda.bpm.engine.task.Task;
 import org.camunda.bpm.engine.test.Deployment;
 import org.camunda.bpm.model.bpmn.Bpmn;
+import org.junit.Test;
 
 /**
  * @author Daniel Meyer
@@ -31,8 +34,9 @@
  */
 public class ActivityInstanceCountMetricsTest extends AbstractMetricsTest {
 
+  @Test
   public void testBpmnActivityInstances() {
-    deployment(Bpmn.createExecutableProcess("testProcess")
+    testRule.deploy(Bpmn.createExecutableProcess("testProcess")
       .startEvent()
       .manualTask()
       .endEvent()
@@ -63,6 +67,7 @@ public void testBpmnActivityInstances() {
         .sum());
   }
 
+  @Test
   public void testStandaloneTask() {
 
     // given
@@ -100,6 +105,7 @@ public void testStandaloneTask() {
   }
 
   @Deployment
+  @Test
   public void testCmmnActivitiyInstances() {
     // given
     // that no activity instances have been executed
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/DecisionMetricsTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/DecisionMetricsTest.java
new file mode 100644
index 00000000000..ab0a6e2ff59
--- /dev/null
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/DecisionMetricsTest.java
@@ -0,0 +1,175 @@
+/*
+ * Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH
+ * under one or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership. Camunda licenses this file to you under the Apache License,
+ * Version 2.0; 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.
+ */
+package org.camunda.bpm.engine.test.api.mgmt.metrics;
+
+import static org.junit.Assert.assertEquals;
+
+import org.camunda.bpm.dmn.engine.impl.DefaultDmnEngineConfiguration;
+import org.camunda.bpm.dmn.engine.spi.DmnEngineMetricCollector;
+import org.camunda.bpm.engine.DecisionService;
+import org.camunda.bpm.engine.management.Metrics;
+import org.camunda.bpm.engine.test.Deployment;
+import org.camunda.bpm.engine.test.util.ResetDmnConfigUtil;
+import org.camunda.bpm.engine.variable.VariableMap;
+import org.camunda.bpm.engine.variable.Variables;
+import org.camunda.bpm.model.bpmn.Bpmn;
+import org.camunda.bpm.model.bpmn.BpmnModelInstance;
+import org.camunda.bpm.model.bpmn.instance.BusinessRuleTask;
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.Test;
+
+public class DecisionMetricsTest extends AbstractMetricsTest {
+
+  public static final String DECISION_DEFINITION_KEY = "decision";
+  public static final String DRD_DISH_DECISION_TABLE = "org/camunda/bpm/engine/test/dmn/deployment/drdDish.dmn11.xml";
+  public static final String DMN_DECISION_LITERAL_EXPRESSION = "org/camunda/bpm/engine/test/api/dmn/DecisionWithLiteralExpression.dmn";
+  public static final String DMN_FILE = "org/camunda/bpm/engine/test/api/mgmt/metrics/ExecutedDecisionElementsTest.dmn11.xml";
+  public static VariableMap VARIABLES = Variables.createVariables().putValue("status", "").putValue("sum", 100);
+
+  protected DecisionService decisionService;
+
+  @Before
+  public void setUp() {
+    DefaultDmnEngineConfiguration dmnEngineConfiguration = processEngineConfiguration
+        .getDmnEngineConfiguration();
+    ResetDmnConfigUtil.reset(dmnEngineConfiguration)
+        .enableFeelLegacyBehavior(true)
+        .init();
+
+    decisionService = engineRule.getDecisionService();
+  }
+
+  @After
+  public void restore() {
+    DefaultDmnEngineConfiguration dmnEngineConfiguration = processEngineConfiguration
+        .getDmnEngineConfiguration();
+    ResetDmnConfigUtil.reset(dmnEngineConfiguration)
+        .enableFeelLegacyBehavior(false)
+        .init();
+  }
+
+  @Override
+  protected void clearMetrics() {
+    super.clearMetrics();
+    DmnEngineMetricCollector metricCollector = processEngineConfiguration.getDmnEngineConfiguration()
+      .getEngineMetricCollector();
+    metricCollector.clearExecutedDecisionInstances();
+    metricCollector.clearExecutedDecisionElements();
+  }
+
+  @Test
+  public void testBusinessRuleTask() {
+    BpmnModelInstance modelInstance = Bpmn.createExecutableProcess("testProcess")
+        .startEvent()
+        .businessRuleTask("task")
+        .endEvent()
+        .done();
+
+    BusinessRuleTask task = modelInstance.getModelElementById("task");
+    task.setCamundaDecisionRef("decision");
+
+    testRule.deploy(repositoryService.createDeployment()
+        .addModelInstance("process.bpmn", modelInstance)
+        .addClasspathResource(DMN_FILE));
+
+    assertEquals(0l, getExecutedDecisionInstances());
+    assertEquals(0l, getExecutedDecisionElements());
+    assertEquals(0l, getExecutedDecisionInstancesFromDmnEngine());
+    assertEquals(0l, getExecutedDecisionElementsFromDmnEngine());
+
+    runtimeService.startProcessInstanceByKey("testProcess", VARIABLES);
+
+    assertEquals(1l, getExecutedDecisionInstances());
+    assertEquals(16l, getExecutedDecisionElements());
+    assertEquals(1l, getExecutedDecisionInstancesFromDmnEngine());
+    assertEquals(16l, getExecutedDecisionElementsFromDmnEngine());
+
+    processEngineConfiguration.getDbMetricsReporter().reportNow();
+
+    assertEquals(1l, getExecutedDecisionInstances());
+    assertEquals(16l, getExecutedDecisionElements());
+    assertEquals(1l, getExecutedDecisionInstancesFromDmnEngine());
+    assertEquals(16l, getExecutedDecisionElementsFromDmnEngine());
+  }
+
+  @Test
+  @Deployment(resources = DMN_DECISION_LITERAL_EXPRESSION)
+  public void shouldCountDecisionLiteralExpression() {
+    // given
+
+    // when
+    decisionService
+        .evaluateDecisionByKey(DECISION_DEFINITION_KEY)
+        .variables(VARIABLES)
+        .evaluate();
+
+    // then
+    assertEquals(1l, getExecutedDecisionInstances());
+
+    processEngineConfiguration.getDbMetricsReporter().reportNow();
+
+    assertEquals(1l, getExecutedDecisionInstances());
+  }
+
+  @Test
+  @Deployment(resources = DRD_DISH_DECISION_TABLE)
+  public void shouldCountDecisionDRG() {
+    // given
+
+    // when
+    decisionService
+        .evaluateDecisionByKey("dish-decision")
+        .variables(VARIABLES
+                       .putValue("temperature", 32)
+                       .putValue("dayType", "Weekend"))
+        .evaluate();
+
+    // then
+    assertEquals(3l, getExecutedDecisionInstances());
+
+    processEngineConfiguration.getDbMetricsReporter().reportNow();
+
+    assertEquals(3l, getExecutedDecisionInstances());
+  }
+
+  protected long getExecutedDecisionInstances() {
+    return managementService.createMetricsQuery()
+        .name(Metrics.EXECUTED_DECISION_INSTANCES)
+        .sum();
+  }
+
+  protected long getExecutedDecisionElements() {
+    return managementService.createMetricsQuery()
+        .name(Metrics.EXECUTED_DECISION_ELEMENTS)
+        .sum();
+  }
+
+  protected long getExecutedDecisionInstancesFromDmnEngine() {
+    return processEngineConfiguration.getDmnEngineConfiguration()
+        .getEngineMetricCollector()
+        .getExecutedDecisionInstances();
+  }
+
+  protected long getExecutedDecisionElementsFromDmnEngine() {
+    return processEngineConfiguration.getDmnEngineConfiguration()
+        .getEngineMetricCollector()
+        .getExecutedDecisionElements();
+  }
+
+}
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ExecutedDecisionElementsMetricsTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ExecutedDecisionElementsMetricsTest.java
deleted file mode 100644
index 205c3d085e8..00000000000
--- a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/ExecutedDecisionElementsMetricsTest.java
+++ /dev/null
@@ -1,80 +0,0 @@
-/*
- * Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH
- * under one or more contributor license agreements. See the NOTICE file
- * distributed with this work for additional information regarding copyright
- * ownership. Camunda licenses this file to you under the Apache License,
- * Version 2.0; 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.
- */
-package org.camunda.bpm.engine.test.api.mgmt.metrics;
-
-import org.camunda.bpm.engine.management.Metrics;
-import org.camunda.bpm.engine.variable.VariableMap;
-import org.camunda.bpm.engine.variable.Variables;
-import org.camunda.bpm.model.bpmn.Bpmn;
-import org.camunda.bpm.model.bpmn.BpmnModelInstance;
-import org.camunda.bpm.model.bpmn.instance.BusinessRuleTask;
-
-public class ExecutedDecisionElementsMetricsTest extends AbstractMetricsTest {
-
-  public static final String DMN_FILE = "org/camunda/bpm/engine/test/api/mgmt/metrics/ExecutedDecisionElementsTest.dmn11.xml";
-  public static VariableMap VARIABLES = Variables.createVariables().putValue("status", "").putValue("sum", 100);
-
-  @Override
-  protected void clearMetrics() {
-    super.clearMetrics();
-    processEngineConfiguration.getDmnEngineConfiguration()
-      .getEngineMetricCollector()
-      .clearExecutedDecisionElements();
-  }
-
-  public void testBusinessRuleTask() {
-    BpmnModelInstance modelInstance = Bpmn.createExecutableProcess("testProcess")
-        .startEvent()
-        .businessRuleTask("task")
-        .endEvent()
-        .done();
-
-    BusinessRuleTask task = modelInstance.getModelElementById("task");
-    task.setCamundaDecisionRef("decision");
-
-    deploymentId = repositoryService.createDeployment()
-        .addModelInstance("process.bpmn", modelInstance)
-        .addClasspathResource(DMN_FILE)
-        .deploy().getId();
-
-    assertEquals(0l, getExecutedDecisionElements());
-    assertEquals(0l, getExecutedDecisionElementsFromDmnEngine());
-
-    runtimeService.startProcessInstanceByKey("testProcess", VARIABLES);
-
-    assertEquals(16l, getExecutedDecisionElements());
-    assertEquals(16l, getExecutedDecisionElementsFromDmnEngine());
-
-    processEngineConfiguration.getDbMetricsReporter().reportNow();
-
-    assertEquals(16l, getExecutedDecisionElements());
-    assertEquals(16l, getExecutedDecisionElementsFromDmnEngine());
-  }
-
-  protected long getExecutedDecisionElements() {
-    return managementService.createMetricsQuery()
-        .name(Metrics.EXECUTED_DECISION_ELEMENTS)
-        .sum();
-  }
-
-  protected long getExecutedDecisionElementsFromDmnEngine() {
-    return processEngineConfiguration.getDmnEngineConfiguration()
-        .getEngineMetricCollector()
-        .getExecutedDecisionElements();
-  }
-
-}
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/JobExecutorMetricsTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/JobExecutorMetricsTest.java
index cd8af9af3b8..ba237f9d099 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/JobExecutorMetricsTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/JobExecutorMetricsTest.java
@@ -16,12 +16,16 @@
  */
 package org.camunda.bpm.engine.test.api.mgmt.metrics;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.RejectedExecutionException;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
+import org.camunda.bpm.engine.ProcessEngine;
 import org.camunda.bpm.engine.impl.ProcessEngineImpl;
 import org.camunda.bpm.engine.impl.jobexecutor.CallerRunsRejectedJobsHandler;
 import org.camunda.bpm.engine.impl.jobexecutor.DefaultJobExecutor;
@@ -31,6 +35,9 @@
 import org.camunda.bpm.engine.test.concurrency.ConcurrencyTestCase.ThreadControl;
 import org.camunda.bpm.engine.test.jobexecutor.ControllableJobExecutor;
 import org.camunda.bpm.engine.variable.Variables;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
 
 
 /**
@@ -39,20 +46,22 @@
  */
 public class JobExecutorMetricsTest extends AbstractMetricsTest {
 
-  protected JobExecutor jobExecutor;
-  protected ThreadPoolExecutor jobThreadPoolExecutor;
+  protected JobExecutor defaultJobExecutor;
+  protected ProcessEngine processEngine;
 
-  protected void setUp() throws Exception {
-    super.setUp();
-    jobExecutor = processEngineConfiguration.getJobExecutor();
+  @Before
+  public void saveJobExecutor() throws Exception {
+    processEngine = engineRule.getProcessEngine();
+    defaultJobExecutor = processEngineConfiguration.getJobExecutor();
   }
 
-  protected void tearDown() throws Exception {
-    super.tearDown();
-    processEngineConfiguration.setJobExecutor(jobExecutor);
+  @After
+  public void restoreJobExecutor() throws Exception {
+    processEngineConfiguration.setJobExecutor(defaultJobExecutor);
   }
 
   @Deployment(resources = "org/camunda/bpm/engine/test/api/mgmt/metrics/asyncServiceTaskProcess.bpmn20.xml")
+  @Test
   public void testJobAcquisitionMetricReporting() {
 
     // given
@@ -61,7 +70,7 @@ public void testJobAcquisitionMetricReporting() {
     }
 
     // when
-    waitForJobExecutorToProcessAllJobs(5000);
+    testRule.waitForJobExecutorToProcessAllJobs(5000);
     processEngineConfiguration.getDbMetricsReporter().reportNow();
 
     // then
@@ -74,6 +83,7 @@ public void testJobAcquisitionMetricReporting() {
   }
 
   @Deployment(resources = "org/camunda/bpm/engine/test/api/mgmt/metrics/asyncServiceTaskProcess.bpmn20.xml")
+  @Test
   public void testCompetingJobAcquisitionMetricReporting() {
     // given
     for (int i = 0; i < 3; i++) {
@@ -125,6 +135,7 @@ public void testCompetingJobAcquisitionMetricReporting() {
   }
 
   @Deployment(resources = "org/camunda/bpm/engine/test/api/mgmt/metrics/asyncServiceTaskProcess.bpmn20.xml")
+  @Test
   public void testJobExecutionMetricReporting() {
     // given
     for (int i = 0; i < 3; i++) {
@@ -136,7 +147,7 @@ public void testJobExecutionMetricReporting() {
     }
 
     // when
-    waitForJobExecutorToProcessAllJobs(5000);
+    testRule.waitForJobExecutorToProcessAllJobs(5000);
 
     // then
     long jobsSuccessful = managementService.createMetricsQuery().name(Metrics.JOB_SUCCESSFUL).sum();
@@ -152,6 +163,7 @@ public void testJobExecutionMetricReporting() {
   }
 
   @Deployment
+   @Test
   public void testJobExecutionMetricExclusiveFollowUp() {
     // given
     for (int i = 0; i < 3; i++) {
@@ -159,7 +171,7 @@ public void testJobExecutionMetricExclusiveFollowUp() {
     }
 
     // when
-    waitForJobExecutorToProcessAllJobs(5000);
+    testRule.waitForJobExecutorToProcessAllJobs(5000);
 
     // then
     long jobsSuccessful = managementService.createMetricsQuery().name(Metrics.JOB_SUCCESSFUL).sum();
@@ -180,6 +192,7 @@ public void testJobExecutionMetricExclusiveFollowUp() {
   }
 
   @Deployment(resources = "org/camunda/bpm/engine/test/api/mgmt/metrics/asyncServiceTaskProcess.bpmn20.xml")
+  @Test
   public void testJobRejectedExecutionMetricReporting() {
     // replace job executor with one that rejects all jobs
     RejectingJobExecutor rejectingExecutor = new RejectingJobExecutor();
@@ -192,7 +205,7 @@ public void testJobRejectedExecutionMetricReporting() {
     }
 
     // when executing the jobs
-    waitForJobExecutorToProcessAllJobs(5000L);
+    testRule.waitForJobExecutorToProcessAllJobs(5000L);
 
     // then all of them were rejected by the job executor which is reflected by the metric
     long numRejectedJobs = managementService.createMetricsQuery().name(Metrics.JOB_EXECUTION_REJECTED).sum();
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsDisabledTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsDisabledTest.java
index 1385bfbcc03..b482038a59a 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsDisabledTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsDisabledTest.java
@@ -16,8 +16,22 @@
  */
 package org.camunda.bpm.engine.test.api.mgmt.metrics;
 
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.fail;
+
+import org.camunda.bpm.engine.ManagementService;
 import org.camunda.bpm.engine.ProcessEngineException;
-import org.camunda.bpm.engine.impl.test.ResourceProcessEngineTestCase;
+import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
+import org.camunda.bpm.engine.test.ProcessEngineRule;
+import org.camunda.bpm.engine.test.util.ProcessEngineBootstrapRule;
+import org.camunda.bpm.engine.test.util.ProcessEngineTestRule;
+import org.camunda.bpm.engine.test.util.ProvidedProcessEngineRule;
+import org.junit.Before;
+import org.junit.ClassRule;
+import org.junit.Ignore;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.RuleChain;
 
 /**
  * Asserts engine functionality is metrics are disabled
@@ -25,14 +39,31 @@
  * @author Daniel Meyer
  *
  */
-public class MetricsDisabledTest extends ResourceProcessEngineTestCase {
+public class MetricsDisabledTest {
+
+  @ClassRule
+  public final static ProcessEngineBootstrapRule bootstrapRule =
+      new ProcessEngineBootstrapRule("org/camunda/bpm/engine/test/api/mgmt/metrics/metricsDisabledTest.cfg.xml");
+
+  protected final ProcessEngineRule engineRule = new ProvidedProcessEngineRule(bootstrapRule);
+  protected final ProcessEngineTestRule testRule = new ProcessEngineTestRule(engineRule);
+
+  @Rule
+  public RuleChain ruleChain = RuleChain.outerRule(engineRule).around(testRule);
+
+  protected ProcessEngineConfigurationImpl processEngineConfiguration;
+  protected ManagementService managementService;
 
-  public MetricsDisabledTest() {
-    super("org/camunda/bpm/engine/test/api/mgmt/metrics/metricsDisabledTest.cfg.xml");
+  @Before
+  public void setUp() {
+    processEngineConfiguration = engineRule.getProcessEngineConfiguration();
+    managementService = engineRule.getManagementService();
   }
 
   // FAILING, see https://app.camunda.com/jira/browse/CAM-4053
   // (to run, remove "FAILING" from methodname)
+  @Ignore
+  @Test
   public void FAILING_testQueryMetricsIfMetricsIsDisabled() {
 
     // given
@@ -46,6 +77,7 @@ public void FAILING_testQueryMetricsIfMetricsIsDisabled() {
 
   }
 
+  @Test
   public void testReportNowIfMetricsDisabled() {
 
     // given
@@ -58,7 +90,7 @@ public void testReportNowIfMetricsDisabled() {
       managementService.reportDbMetricsNow();
       fail("Exception expected");
     } catch(ProcessEngineException e) {
-      assertTextPresent("Metrics reporting is disabled", e.getMessage());
+      testRule.assertTextPresent("Metrics reporting is disabled", e.getMessage());
     }
   }
 }
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsTest.java
index 89088d50ad2..00466d59616 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/MetricsTest.java
@@ -16,12 +16,15 @@
  */
 package org.camunda.bpm.engine.test.api.mgmt.metrics;
 
-import java.util.Collection;
-import java.util.Date;
 import static junit.framework.TestCase.assertEquals;
 import static junit.framework.TestCase.fail;
-import org.camunda.bpm.engine.ManagementService;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertTrue;
 
+import java.util.Collection;
+import java.util.Date;
+
+import org.camunda.bpm.engine.ManagementService;
 import org.camunda.bpm.engine.ProcessEngineException;
 import org.camunda.bpm.engine.RuntimeService;
 import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
@@ -33,8 +36,6 @@
 import org.camunda.bpm.engine.test.util.ProvidedProcessEngineRule;
 import org.camunda.bpm.model.bpmn.Bpmn;
 import org.junit.After;
-import org.junit.Assert;
-import static org.junit.Assert.assertNotEquals;
 import org.junit.BeforeClass;
 import org.junit.ClassRule;
 import org.junit.Test;
@@ -148,8 +149,8 @@ public void testDeleteMetrics() {
     runtimeService.startProcessInstanceByKey("testProcess");
     processEngineConfiguration.getDbMetricsReporter().reportNow();
 
-    // a count of six (start and end)
-    assertEquals(6l, managementService.createMetricsQuery()
+    // a count of 7 (start, end and root process instance)
+    assertEquals(7l, managementService.createMetricsQuery()
             .sum());
 
     // if
@@ -168,8 +169,8 @@ public void testDeleteMetricsWithTimestamp() {
     runtimeService.startProcessInstanceByKey("testProcess");
     processEngineConfiguration.getDbMetricsReporter().reportNow();
 
-    // a count of six (start and end)
-    assertEquals(6l, managementService.createMetricsQuery()
+    // a count of 7 (start, end and root process instance)
+    assertEquals(7l, managementService.createMetricsQuery()
             .sum());
 
     // if
@@ -190,8 +191,8 @@ public void testDeleteMetricsWithTimestampBefore() {
     runtimeService.startProcessInstanceByKey("testProcess");
     processEngineConfiguration.getDbMetricsReporter().reportNow();
 
-    // a count of six (start and end)
-    assertEquals(6l, managementService.createMetricsQuery()
+    // a count of 7 (start, end and root process instance)
+    assertEquals(7l, managementService.createMetricsQuery()
             .sum());
 
     // if
@@ -200,7 +201,7 @@ public void testDeleteMetricsWithTimestampBefore() {
 
     // then
     // the entires are NOT deleted
-    assertEquals(6l, managementService.createMetricsQuery()
+    assertEquals(7l, managementService.createMetricsQuery()
             .sum());
   }
 
@@ -268,7 +269,7 @@ public void testReportNowIfMetricsIsDisabled() {
     }
     catch (ProcessEngineException e) {
       // then an exception is thrown
-      Assert.assertTrue(e.getMessage().contains("Metrics reporting is disabled"));
+      assertTrue(e.getMessage().contains("Metrics reporting is disabled"));
     }
     finally {
       // reset metrics setting
@@ -292,7 +293,7 @@ public void testReportNowIfReporterIsNotActive() {
     }
     catch (ProcessEngineException e) {
       // then an exception is thrown
-      Assert.assertTrue(e.getMessage().contains("Metrics reporting to database is disabled"));
+      assertTrue(e.getMessage().contains("Metrics reporting to database is disabled"));
     } finally {
       processEngineConfiguration.setMetricsEnabled(defaultIsMetricsEnabled);
       processEngineConfiguration.setDbMetricsReporterActivate(defaultIsMetricsReporterActivate);
@@ -309,9 +310,9 @@ public void testQuery() {
     assertEquals(0l, managementService.createMetricsQuery().name("UNKNOWN").sum());
     assertEquals(3l, managementService.createMetricsQuery().name(Metrics.ACTIVTY_INSTANCE_START).sum());
 
-    assertEquals(6l, managementService.createMetricsQuery().sum());
-    assertEquals(6l, managementService.createMetricsQuery().startDate(new Date(1000)).sum());
-    assertEquals(6l, managementService.createMetricsQuery().startDate(new Date(1000))
+    assertEquals(7l, managementService.createMetricsQuery().sum());
+    assertEquals(7l, managementService.createMetricsQuery().startDate(new Date(1000)).sum());
+    assertEquals(7l, managementService.createMetricsQuery().startDate(new Date(1000))
             .endDate(new Date(ClockUtil.getCurrentTime().getTime() + 2000l)).sum()); // + 2000 for milliseconds imprecision on some databases (MySQL)
     assertEquals(0l, managementService.createMetricsQuery().startDate(new Date(ClockUtil.getCurrentTime().getTime() + 1000l)).sum());
     assertEquals(0l, managementService.createMetricsQuery().startDate(new Date(ClockUtil.getCurrentTime().getTime() + 1000l)).endDate(ClockUtil.getCurrentTime()).sum());
@@ -321,9 +322,9 @@ public void testQuery() {
     processEngineConfiguration.getDbMetricsReporter().reportNow();
 
     // then (query assertions)
-    assertEquals(12l, managementService.createMetricsQuery().sum());
-    assertEquals(12l, managementService.createMetricsQuery().startDate(new Date(1000)).sum());
-    assertEquals(12l, managementService.createMetricsQuery().startDate(new Date(1000)).endDate(new Date(ClockUtil.getCurrentTime().getTime() + 2000l)).sum()); // + 2000 for milliseconds imprecision on some databases (MySQL)
+    assertEquals(14l, managementService.createMetricsQuery().sum());
+    assertEquals(14l, managementService.createMetricsQuery().startDate(new Date(1000)).sum());
+    assertEquals(14l, managementService.createMetricsQuery().startDate(new Date(1000)).endDate(new Date(ClockUtil.getCurrentTime().getTime() + 2000l)).sum()); // + 2000 for milliseconds imprecision on some databases (MySQL)
     assertEquals(0l, managementService.createMetricsQuery().startDate(new Date(ClockUtil.getCurrentTime().getTime() + 1000l)).sum());
     assertEquals(0l, managementService.createMetricsQuery().startDate(new Date(ClockUtil.getCurrentTime().getTime() + 1000l)).endDate(ClockUtil.getCurrentTime()).sum());
   }
@@ -347,10 +348,10 @@ public void testQueryEndDateExclusive() {
     processEngineConfiguration.getDbMetricsReporter().reportNow();
 
     // then Query#startDate is inclusive and Query#endDate is exclusive
-    assertEquals(18l, managementService.createMetricsQuery().sum());
-    assertEquals(18l, managementService.createMetricsQuery().startDate(new Date(0)).sum());
-    assertEquals(12l, managementService.createMetricsQuery().startDate(new Date(0)).endDate(new Date(7000L)).sum());
-    assertEquals(18l, managementService.createMetricsQuery().startDate(new Date(0)).endDate(new Date(8000L)).sum());
+    assertEquals(21l, managementService.createMetricsQuery().sum());
+    assertEquals(21l, managementService.createMetricsQuery().startDate(new Date(0)).sum());
+    assertEquals(14l, managementService.createMetricsQuery().startDate(new Date(0)).endDate(new Date(7000L)).sum());
+    assertEquals(21l, managementService.createMetricsQuery().startDate(new Date(0)).endDate(new Date(8000L)).sum());
 
   }
 
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/RootProcessInstanceMetricsTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/RootProcessInstanceMetricsTest.java
new file mode 100644
index 00000000000..98bfe79e112
--- /dev/null
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/mgmt/metrics/RootProcessInstanceMetricsTest.java
@@ -0,0 +1,145 @@
+/*
+ * Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH
+ * under one or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership. Camunda licenses this file to you under the Apache License,
+ * Version 2.0; 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.
+ */
+package org.camunda.bpm.engine.test.api.mgmt.metrics;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.Collections;
+import java.util.Map;
+
+import org.camunda.bpm.engine.management.Metrics;
+import org.camunda.bpm.engine.management.MetricsQuery;
+import org.camunda.bpm.engine.variable.VariableMap;
+import org.camunda.bpm.engine.variable.Variables;
+import org.camunda.bpm.model.bpmn.Bpmn;
+import org.camunda.bpm.model.bpmn.BpmnModelInstance;
+import org.camunda.bpm.model.bpmn.instance.CallActivity;
+import org.junit.Test;
+
+public class RootProcessInstanceMetricsTest extends AbstractMetricsTest {
+
+  public static final String DMN_FILE
+      = "org/camunda/bpm/engine/test/api/mgmt/metrics/ExecutedDecisionElementsTest.dmn11.xml";
+  public static VariableMap VARIABLES = Variables.createVariables()
+      .putValue("status", "")
+      .putValue("sum", 100);
+
+  protected static final String BASE_INSTANCE_KEY = "baseProcess";
+  protected static final BpmnModelInstance BASE_INSTANCE = Bpmn.createExecutableProcess(BASE_INSTANCE_KEY)
+      .startEvent()
+      .endEvent()
+      .done();
+
+  protected static final String CALLED_DMN_INSTANCE_KEY = "calledDMNProcess";
+  protected static final BpmnModelInstance CALLED_DMN_INSTANCE = Bpmn.createExecutableProcess(CALLED_DMN_INSTANCE_KEY)
+      .startEvent()
+      .businessRuleTask()
+        .camundaDecisionRef("decision")
+      .endEvent()
+      .done();
+
+  protected static final String CALLING_INSTANCE_KEY = "callingProcess";
+
+  @Override
+  protected void clearMetrics() {
+    super.clearMetrics();
+    processEngineConfiguration.getDmnEngineConfiguration()
+        .getEngineMetricCollector()
+        .clearExecutedDecisionElements();
+  }
+
+  @Test
+  public void shouldCountOneRootProcessInstance() {
+    // given
+    testRule.deploy(BASE_INSTANCE);
+
+    // when
+    runtimeService.startProcessInstanceByKey(BASE_INSTANCE_KEY);
+
+    // then
+    MetricsQuery query = managementService.createMetricsQuery();
+    assertEquals(1l, query.name(Metrics.ROOT_PROCESS_INSTANCE_START).sum());
+
+    // and force the db metrics reporter to report
+    processEngineConfiguration.getDbMetricsReporter().reportNow();
+
+    // still 1
+    assertEquals(1l, query.name(Metrics.ROOT_PROCESS_INSTANCE_START).sum());
+  }
+
+  @Test
+  public void shouldCountRootProcessInstanceWithCallActivities() {
+    // given
+    BpmnModelInstance callingInstance = getCallingInstance(BASE_INSTANCE_KEY, Collections.EMPTY_MAP);
+    testRule.deploy(BASE_INSTANCE, callingInstance);
+
+    // when
+    runtimeService.startProcessInstanceByKey(CALLING_INSTANCE_KEY);
+
+    // then
+    MetricsQuery query = managementService.createMetricsQuery();
+    assertEquals(1l, query.name(Metrics.ROOT_PROCESS_INSTANCE_START).sum());
+
+    // and force the db metrics reporter to report
+    processEngineConfiguration.getDbMetricsReporter().reportNow();
+
+    // still 1
+    assertEquals(1l, query.name(Metrics.ROOT_PROCESS_INSTANCE_START).sum());
+  }
+
+  @Test
+  public void shouldCountRootProcessInstanceAndDecisionInstanceWithBusinessRuleTask() {
+    // given
+    BpmnModelInstance callingInstance = getCallingInstance(CALLED_DMN_INSTANCE_KEY, VARIABLES);
+    testRule.deploy(repositoryService.createDeployment()
+                        .addClasspathResource(DMN_FILE)
+                        .addModelInstance("calledProcess.bpmn", CALLED_DMN_INSTANCE)
+                        .addModelInstance("callingProcess.bpmn", callingInstance));
+
+    // when
+    runtimeService.startProcessInstanceByKey(CALLING_INSTANCE_KEY, VARIABLES);
+
+    // then
+    MetricsQuery query = managementService.createMetricsQuery();
+    assertEquals(1l, query.name(Metrics.ROOT_PROCESS_INSTANCE_START).sum());
+    assertEquals(1l, query.name(Metrics.EXECUTED_DECISION_INSTANCES).sum());
+
+    // and force the db metrics reporter to report
+    processEngineConfiguration.getDbMetricsReporter().reportNow();
+
+    // still 1
+    assertEquals(1l, query.name(Metrics.ROOT_PROCESS_INSTANCE_START).sum());
+    assertEquals(1l, query.name(Metrics.EXECUTED_DECISION_INSTANCES).sum());
+  }
+
+  protected BpmnModelInstance getCallingInstance(String calledInstanceKey, Map variables) {
+    BpmnModelInstance modelInstance = Bpmn.createExecutableProcess(CALLING_INSTANCE_KEY)
+        .startEvent()
+        .callActivity("calledProcess")
+          .calledElement(calledInstanceKey)
+        .endEvent()
+        .done();
+
+    // pass any variables to the call activity
+    CallActivity callActivity = modelInstance.getModelElementById("calledProcess");
+    variables.keySet()
+        .iterator()
+        .forEachRemaining(name -> callActivity.builder().camundaIn((String) name, (String) name));
+
+    return modelInstance;
+  }
+}
\ No newline at end of file
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/standalone/db/entitymanager/PurgeDatabaseTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/standalone/db/entitymanager/PurgeDatabaseTest.java
index 988d262b83e..7ed81f800dc 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/standalone/db/entitymanager/PurgeDatabaseTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/standalone/db/entitymanager/PurgeDatabaseTest.java
@@ -199,7 +199,7 @@ public void testPurgeComplexProcess() {
     assertEquals(2, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_RU_JOBDEF"));
     assertEquals(2, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_ID_USER"));
     assertEquals(5, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_RU_EXECUTION"));
-    assertEquals(10, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_RU_METER_LOG"));
+    assertEquals(12, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_RU_METER_LOG"));
     assertEquals(1, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_RU_VARIABLE"));
     assertEquals(1, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_RE_PROCDEF"));
     assertEquals(2, (long) databasePurgeReport.getReportValue(databaseTablePrefix + "ACT_ID_TENANT"));