SONAR-11873 Memory leak when Compute Engine persists file duplications

4 files changed, 261 insertions, 159 deletions

diff --git a/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/DuplicationDataMeasuresStep.java b/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/PersistDuplicationDataStep.java
index 3a43ce68988..3745038f03f 100644
--- a/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/DuplicationDataMeasuresStep.java
+++ b/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/PersistDuplicationDataStep.java
@@ -19,6 +19,8 @@
  */
 package org.sonar.ce.task.projectanalysis.step;
 
+import java.util.ArrayList;
+import java.util.List;
 import org.apache.commons.lang.StringEscapeUtils;
 import org.sonar.ce.task.projectanalysis.component.Component;
 import org.sonar.ce.task.projectanalysis.component.CrawlerDepthLimit;
@@ -34,10 +36,13 @@ import org.sonar.ce.task.projectanalysis.duplication.InProjectDuplicate;
 import org.sonar.ce.task.projectanalysis.duplication.InnerDuplicate;
 import org.sonar.ce.task.projectanalysis.duplication.TextBlock;
 import org.sonar.ce.task.projectanalysis.measure.Measure;
-import org.sonar.ce.task.projectanalysis.measure.MeasureRepository;
+import org.sonar.ce.task.projectanalysis.measure.MeasureToMeasureDto;
 import org.sonar.ce.task.projectanalysis.metric.Metric;
 import org.sonar.ce.task.projectanalysis.metric.MetricRepository;
 import org.sonar.ce.task.step.ComputationStep;
+import org.sonar.db.DbClient;
+import org.sonar.db.DbSession;
+import org.sonar.db.measure.LiveMeasureDto;
 
 import static com.google.common.collect.Iterables.isEmpty;
 import static org.sonar.api.measures.CoreMetrics.DUPLICATIONS_DATA_KEY;
@@ -46,32 +51,50 @@ import static org.sonar.ce.task.projectanalysis.component.ComponentVisitor.Order
 /**
  * Compute duplication data measures on files, based on the {@link DuplicationRepository}
  */
-public class DuplicationDataMeasuresStep implements ComputationStep {
+public class PersistDuplicationDataStep implements ComputationStep {
 
-  private final MeasureRepository measureRepository;
+  private final DbClient dbClient;
   private final TreeRootHolder treeRootHolder;
   private final DuplicationRepository duplicationRepository;
-
+  private final MeasureToMeasureDto measureToMeasureDto;
   private final Metric duplicationDataMetric;
 
-  public DuplicationDataMeasuresStep(TreeRootHolder treeRootHolder, MetricRepository metricRepository, MeasureRepository measureRepository,
-    DuplicationRepository duplicationRepository) {
-    this.measureRepository = measureRepository;
+  public PersistDuplicationDataStep(DbClient dbClient, TreeRootHolder treeRootHolder, MetricRepository metricRepository,
+    DuplicationRepository duplicationRepository, MeasureToMeasureDto measureToMeasureDto) {
+    this.dbClient = dbClient;
     this.treeRootHolder = treeRootHolder;
     this.duplicationRepository = duplicationRepository;
+    this.measureToMeasureDto = measureToMeasureDto;
     this.duplicationDataMetric = metricRepository.getByKey(DUPLICATIONS_DATA_KEY);
   }
 
   @Override
   public void execute(ComputationStep.Context context) {
-    new DepthTraversalTypeAwareCrawler(new DuplicationVisitor())
-      .visit(treeRootHolder.getRoot());
+    boolean supportUpsert = dbClient.getDatabase().getDialect().supportsUpsert();
+
+    // batch mode of DB session does not have benefits:
+    // - on postgres the multi-row upserts are the major optimization and have exactly the same
+    //   performance between batch and non-batch sessions
+    // - on other dbs the sequence of inserts and updates, in order to emulate upserts,
+    //   breaks the constraint of batch sessions (consecutive requests should have the same
+    //   structure (same PreparedStatement))
+    try (DbSession dbSession = dbClient.openSession(false);
+      DuplicationVisitor visitor = new DuplicationVisitor(dbSession, supportUpsert)) {
+      new DepthTraversalTypeAwareCrawler(visitor).visit(treeRootHolder.getRoot());
+      context.getStatistics().add("insertsOrUpdates", visitor.insertsOrUpdates);
+    }
   }
 
-  private class DuplicationVisitor extends TypeAwareVisitorAdapter {
+  private class DuplicationVisitor extends TypeAwareVisitorAdapter implements AutoCloseable {
+    private final DbSession dbSession;
+    private final boolean supportUpsert;
+    private final List<LiveMeasureDto> nonPersistedBuffer = new ArrayList<>();
+    private int insertsOrUpdates = 0;
 
-    private DuplicationVisitor() {
+    private DuplicationVisitor(DbSession dbSession, boolean supportUpsert) {
       super(CrawlerDepthLimit.FILE, PRE_ORDER);
+      this.dbSession = dbSession;
+      this.supportUpsert = supportUpsert;
     }
 
     @Override
@@ -83,14 +106,41 @@ public class DuplicationDataMeasuresStep implements ComputationStep {
     }
 
     private void computeDuplications(Component component, Iterable<Duplication> duplications) {
-      String duplicationXml = createXmlDuplications(component.getDbKey(), duplications);
-      measureRepository.add(
-        component,
-        duplicationDataMetric,
-        Measure.newMeasureBuilder().create(duplicationXml));
+      Measure measure = generateMeasure(component.getDbKey(), duplications);
+      LiveMeasureDto dto = measureToMeasureDto.toLiveMeasureDto(measure, duplicationDataMetric, component);
+      nonPersistedBuffer.add(dto);
+      persist(false);
+    }
+
+    private void persist(boolean force) {
+      // Persist a bunch of 100 or less measures. That prevents from having more than 100 XML documents
+      // in memory. Consumption of memory does not explode with the number of duplications and is kept
+      // under control.
+      // Measures are upserted and transactions are committed every 100 rows (arbitrary number to
+      // maximize the performance of a multi-rows request on PostgreSQL).
+      // On PostgreSQL, a bunch of 100 measures is persisted into a single request (multi-rows upsert).
+      // On other DBs, measures are persisted one by one, with update-or-insert requests.
+      boolean shouldPersist = !nonPersistedBuffer.isEmpty() && (force || nonPersistedBuffer.size() > 100);
+      if (!shouldPersist) {
+        return;
+      }
+      if (supportUpsert) {
+        dbClient.liveMeasureDao().upsert(dbSession, nonPersistedBuffer);
+      } else {
+        nonPersistedBuffer.forEach(d -> dbClient.liveMeasureDao().insertOrUpdate(dbSession, d));
+      }
+      insertsOrUpdates += nonPersistedBuffer.size();
+      nonPersistedBuffer.clear();
+      dbSession.commit();
+    }
+
+    @Override
+    public void close() {
+      // persist the measures remaining in the buffer
+      persist(true);
     }
 
-    private String createXmlDuplications(String componentDbKey, Iterable<Duplication> duplications) {
+    private Measure generateMeasure(String componentDbKey, Iterable<Duplication> duplications) {
       StringBuilder xml = new StringBuilder();
       xml.append("<duplications>");
       for (Duplication duplication : duplications) {
@@ -102,7 +152,7 @@ public class DuplicationDataMeasuresStep implements ComputationStep {
         xml.append("</g>");
       }
       xml.append("</duplications>");
-      return xml.toString();
+      return Measure.newMeasureBuilder().create(xml.toString());
     }
 
     private void processDuplicationBlock(StringBuilder xml, Duplicate duplicate, String componentDbKey) {
@@ -140,7 +190,7 @@ public class DuplicationDataMeasuresStep implements ComputationStep {
 
   @Override
   public String getDescription() {
-    return "Compute duplication data measures";
+    return "Persist duplication data";
   }
 
 }
diff --git a/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/ReportComputationSteps.java b/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/ReportComputationSteps.java
index e1e6b5b0895..ddcac2ab54b 100644
--- a/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/ReportComputationSteps.java
+++ b/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/step/ReportComputationSteps.java
@@ -67,7 +67,6 @@ public class ReportComputationSteps extends AbstractComputationSteps {
     CommentMeasuresStep.class,
     CustomMeasuresCopyStep.class,
     DuplicationMeasuresStep.class,
-    DuplicationDataMeasuresStep.class,
     NewSizeMeasuresStep.class,
     LanguageDistributionMeasuresStep.class,
     UnitTestMeasuresStep.class,
@@ -94,6 +93,7 @@ public class ReportComputationSteps extends AbstractComputationSteps {
     PersistAnalysisPropertiesStep.class,
     PersistMeasuresStep.class,
     PersistLiveMeasuresStep.class,
+    PersistDuplicationDataStep.class,
     PersistAdHocRulesStep.class,
     PersistIssuesStep.class,
     PersistProjectLinksStep.class,
diff --git a/server/sonar-ce-task-projectanalysis/src/test/java/org/sonar/ce/task/projectanalysis/step/DuplicationDataMeasuresStepTest.java b/server/sonar-ce-task-projectanalysis/src/test/java/org/sonar/ce/task/projectanalysis/step/DuplicationDataMeasuresStepTest.java
deleted file mode 100644
index 11518f2674e..00000000000
--- a/server/sonar-ce-task-projectanalysis/src/test/java/org/sonar/ce/task/projectanalysis/step/DuplicationDataMeasuresStepTest.java
+++ /dev/null
@@ -1,139 +0,0 @@
-/*
- * SonarQube
- * Copyright (C) 2009-2019 SonarSource SA
- * mailto:info AT sonarsource DOT com
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
- */
-package org.sonar.ce.task.projectanalysis.step;
-
-import org.junit.Rule;
-import org.junit.Test;
-import org.sonar.ce.task.projectanalysis.component.TreeRootHolderRule;
-import org.sonar.ce.task.projectanalysis.duplication.DuplicationRepositoryRule;
-import org.sonar.ce.task.projectanalysis.duplication.TextBlock;
-import org.sonar.ce.task.projectanalysis.measure.MeasureRepositoryRule;
-import org.sonar.ce.task.projectanalysis.metric.MetricRepositoryRule;
-import org.sonar.ce.task.step.ComputationStep;
-import org.sonar.ce.task.step.TestComputationStepContext;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.sonar.api.measures.CoreMetrics.DUPLICATIONS_DATA;
-import static org.sonar.api.measures.CoreMetrics.DUPLICATIONS_DATA_KEY;
-import static org.sonar.ce.task.projectanalysis.component.Component.Type.FILE;
-import static org.sonar.ce.task.projectanalysis.component.Component.Type.PROJECT;
-import static org.sonar.ce.task.projectanalysis.component.ReportComponent.builder;
-
-public class DuplicationDataMeasuresStepTest extends BaseStepTest {
-
-  private static final int ROOT_REF = 1;
-  private static final String PROJECT_KEY = "PROJECT_KEY";
-
-  private static final int FILE_1_REF = 2;
-  private static final String FILE_1_KEY = "FILE_1_KEY";
-
-  private static final int FILE_2_REF = 3;
-  private static final String FILE_2_KEY = "FILE_2_KEY";
-
-  @Rule
-  public TreeRootHolderRule treeRootHolder = new TreeRootHolderRule()
-    .setRoot(
-      builder(PROJECT, ROOT_REF).setKey(PROJECT_KEY)
-        .addChildren(
-          builder(FILE, FILE_1_REF).setKey(FILE_1_KEY)
-            .build(),
-          builder(FILE, FILE_2_REF).setKey(FILE_2_KEY)
-            .build())
-        .build());
-
-  @Rule
-  public DuplicationRepositoryRule duplicationRepository = DuplicationRepositoryRule.create(treeRootHolder);
-
-  @Rule
-  public MetricRepositoryRule metricRepository = new MetricRepositoryRule()
-    .add(DUPLICATIONS_DATA);
-
-  @Rule
-  public MeasureRepositoryRule measureRepository = MeasureRepositoryRule.create(treeRootHolder, metricRepository);
-
-  private DuplicationDataMeasuresStep underTest = new DuplicationDataMeasuresStep(treeRootHolder, metricRepository, measureRepository, duplicationRepository);
-
-  @Override
-  protected ComputationStep step() {
-    return underTest;
-  }
-
-  @Test
-  public void nothing_to_do_when_no_duplication() {
-    underTest.execute(new TestComputationStepContext());
-
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY)).isNotPresent();
-    assertThat(measureRepository.getAddedRawMeasure(FILE_2_REF, DUPLICATIONS_DATA_KEY)).isNotPresent();
-  }
-
-  @Test
-  public void compute_duplications_on_same_file() {
-    duplicationRepository.addDuplication(FILE_1_REF, new TextBlock(1, 5), new TextBlock(6, 10));
-
-    underTest.execute(new TestComputationStepContext());
-
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY)).isPresent();
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY).get().getData()).isEqualTo(
-      "<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"false\" r=\""
-        + FILE_1_KEY + "\"/></g></duplications>");
-    assertThat(measureRepository.getAddedRawMeasure(FILE_2_REF, DUPLICATIONS_DATA_KEY)).isNotPresent();
-  }
-
-  @Test
-  public void compute_duplications_on_different_files() {
-    duplicationRepository.addDuplication(FILE_1_REF, new TextBlock(1, 5), FILE_2_REF, new TextBlock(6, 10));
-
-    underTest.execute(new TestComputationStepContext());
-
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY)).isPresent();
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY).get().getData()).isEqualTo(
-      "<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"false\" r=\""
-        + FILE_2_KEY + "\"/></g></duplications>");
-    assertThat(measureRepository.getAddedRawMeasure(FILE_2_REF, DUPLICATIONS_DATA_KEY)).isNotPresent();
-  }
-
-  @Test
-  public void compute_duplications_on_unchanged_file() {
-    duplicationRepository.addExtendedProjectDuplication(FILE_1_REF, new TextBlock(1, 5), FILE_2_REF, new TextBlock(6, 10));
-
-    underTest.execute(new TestComputationStepContext());
-
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY)).isPresent();
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY).get().getData()).isEqualTo(
-      "<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"true\" r=\""
-        + FILE_2_KEY + "\"/></g></duplications>");
-    assertThat(measureRepository.getAddedRawMeasure(FILE_2_REF, DUPLICATIONS_DATA_KEY)).isNotPresent();
-  }
-
-  @Test
-  public void compute_duplications_on_different_projects() {
-    String fileKeyFromOtherProject = "PROJECT2_KEY:file2";
-    duplicationRepository.addCrossProjectDuplication(FILE_1_REF, new TextBlock(1, 5), fileKeyFromOtherProject, new TextBlock(6, 10));
-
-    underTest.execute(new TestComputationStepContext());
-
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY)).isPresent();
-    assertThat(measureRepository.getAddedRawMeasure(FILE_1_REF, DUPLICATIONS_DATA_KEY).get().getData()).isEqualTo(
-      "<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"false\" r=\""
-        + fileKeyFromOtherProject + "\"/></g></duplications>");
-    assertThat(measureRepository.getAddedRawMeasure(FILE_2_REF, DUPLICATIONS_DATA_KEY)).isNotPresent();
-  }
-
-}
diff --git a/server/sonar-ce-task-projectanalysis/src/test/java/org/sonar/ce/task/projectanalysis/step/PersistDuplicationDataStepTest.java b/server/sonar-ce-task-projectanalysis/src/test/java/org/sonar/ce/task/projectanalysis/step/PersistDuplicationDataStepTest.java
new file mode 100644
index 00000000000..987c834ad91
--- /dev/null
+++ b/server/sonar-ce-task-projectanalysis/src/test/java/org/sonar/ce/task/projectanalysis/step/PersistDuplicationDataStepTest.java
@@ -0,0 +1,191 @@
+/*
+ * SonarQube
+ * Copyright (C) 2009-2019 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.ce.task.projectanalysis.step;
+
+import java.util.Optional;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.sonar.api.measures.Metric;
+import org.sonar.api.utils.System2;
+import org.sonar.ce.task.projectanalysis.analysis.MutableAnalysisMetadataHolderRule;
+import org.sonar.ce.task.projectanalysis.component.TreeRootHolderRule;
+import org.sonar.ce.task.projectanalysis.duplication.DuplicationRepositoryRule;
+import org.sonar.ce.task.projectanalysis.duplication.TextBlock;
+import org.sonar.ce.task.projectanalysis.measure.MeasureToMeasureDto;
+import org.sonar.ce.task.projectanalysis.metric.MetricRepositoryRule;
+import org.sonar.ce.task.step.ComputationStep;
+import org.sonar.ce.task.step.TestComputationStepContext;
+import org.sonar.db.DbTester;
+import org.sonar.db.component.ComponentDto;
+import org.sonar.db.measure.LiveMeasureDto;
+import org.sonar.db.metric.MetricDto;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.sonar.api.measures.CoreMetrics.DUPLICATIONS_DATA_KEY;
+import static org.sonar.ce.task.projectanalysis.component.Component.Type.FILE;
+import static org.sonar.ce.task.projectanalysis.component.Component.Type.PROJECT;
+import static org.sonar.ce.task.projectanalysis.component.ReportComponent.builder;
+
+public class PersistDuplicationDataStepTest extends BaseStepTest {
+
+  private static final int ROOT_REF = 1;
+  private static final String PROJECT_KEY = "PROJECT_KEY";
+  private static final String PROJECT_UUID = "u1";
+
+  private static final int FILE_1_REF = 2;
+  private static final String FILE_1_KEY = "FILE_1_KEY";
+  private static final String FILE_1_UUID = "u2";
+
+  private static final int FILE_2_REF = 3;
+  private static final String FILE_2_KEY = "FILE_2_KEY";
+  private static final String FILE_2_UUID = "u3";
+
+  @Rule
+  public DbTester db = DbTester.create(System2.INSTANCE);
+  @Rule
+  public TreeRootHolderRule treeRootHolder = new TreeRootHolderRule()
+    .setRoot(
+      builder(PROJECT, ROOT_REF).setKey(PROJECT_KEY).setUuid(PROJECT_UUID)
+        .addChildren(
+          builder(FILE, FILE_1_REF).setKey(FILE_1_KEY).setUuid(FILE_1_UUID)
+            .build(),
+          builder(FILE, FILE_2_REF).setKey(FILE_2_KEY).setUuid(FILE_2_UUID)
+            .build())
+        .build());
+
+  @Rule
+  public MutableAnalysisMetadataHolderRule analysisMetadataHolder = new MutableAnalysisMetadataHolderRule();
+  @Rule
+  public DuplicationRepositoryRule duplicationRepository = DuplicationRepositoryRule.create(treeRootHolder);
+  @Rule
+  public MetricRepositoryRule metricRepository = new MetricRepositoryRule();
+
+  @Before
+  public void setUp() throws Exception {
+    MetricDto metric = db.measures().insertMetric(m -> m.setKey(DUPLICATIONS_DATA_KEY).setValueType(Metric.ValueType.STRING.name()));
+    insertComponent(PROJECT_KEY, PROJECT_UUID);
+    insertComponent(FILE_1_KEY, FILE_1_UUID);
+    insertComponent(FILE_2_KEY, FILE_2_UUID);
+    db.commit();
+    metricRepository.add(metric.getId(), new Metric.Builder(DUPLICATIONS_DATA_KEY, DUPLICATIONS_DATA_KEY, Metric.ValueType.STRING).create());
+  }
+
+  @Override
+  protected ComputationStep step() {
+    return underTest();
+  }
+
+  @Test
+  public void nothing_to_persist_when_no_duplication() {
+    TestComputationStepContext context = new TestComputationStepContext();
+
+    underTest().execute(context);
+
+    assertThatNothingPersisted();
+    verifyStatistics(context, 0);
+  }
+
+  @Test
+  public void compute_duplications_on_same_file() {
+    duplicationRepository.addDuplication(FILE_1_REF, new TextBlock(1, 5), new TextBlock(6, 10));
+    TestComputationStepContext context = new TestComputationStepContext();
+
+    underTest().execute(context);
+
+    assertThat(selectMeasureData(FILE_1_UUID)).hasValue("<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"false\" r=\""
+        + FILE_1_KEY + "\"/></g></duplications>");
+    assertThat(selectMeasureData(FILE_2_UUID)).isEmpty();
+    assertThat(selectMeasureData(PROJECT_UUID)).isEmpty();
+  }
+
+  @Test
+  public void compute_duplications_on_different_files() {
+    duplicationRepository.addDuplication(FILE_1_REF, new TextBlock(1, 5), FILE_2_REF, new TextBlock(6, 10));
+    TestComputationStepContext context = new TestComputationStepContext();
+
+    underTest().execute(context);
+
+    assertThat(selectMeasureData(FILE_1_UUID)).hasValue(
+      "<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"false\" r=\""
+        + FILE_2_KEY + "\"/></g></duplications>");
+    assertThat(selectMeasureData(FILE_2_UUID)).isEmpty();
+    assertThat(selectMeasureData(PROJECT_UUID)).isEmpty();
+  }
+
+  @Test
+  public void compute_duplications_on_unchanged_file() {
+    duplicationRepository.addExtendedProjectDuplication(FILE_1_REF, new TextBlock(1, 5), FILE_2_REF, new TextBlock(6, 10));
+    TestComputationStepContext context = new TestComputationStepContext();
+
+    underTest().execute(context);
+
+    assertThat(selectMeasureData(FILE_1_UUID)).hasValue(
+      "<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"true\" r=\""
+        + FILE_2_KEY + "\"/></g></duplications>");
+    assertThat(selectMeasureData(FILE_2_UUID)).isEmpty();
+    assertThat(selectMeasureData(PROJECT_UUID)).isEmpty();
+  }
+
+  @Test
+  public void compute_duplications_on_different_projects() {
+    String fileKeyFromOtherProject = "PROJECT2_KEY:file2";
+    duplicationRepository.addCrossProjectDuplication(FILE_1_REF, new TextBlock(1, 5), fileKeyFromOtherProject, new TextBlock(6, 10));
+    TestComputationStepContext context = new TestComputationStepContext();
+
+    underTest().execute(context);
+
+    assertThat(selectMeasureData(FILE_1_UUID)).hasValue(
+      "<duplications><g><b s=\"1\" l=\"5\" t=\"false\" r=\"" + FILE_1_KEY + "\"/><b s=\"6\" l=\"5\" t=\"false\" r=\""
+        + fileKeyFromOtherProject + "\"/></g></duplications>");
+    assertThat(selectMeasureData(FILE_2_UUID)).isEmpty();
+    assertThat(selectMeasureData(PROJECT_UUID)).isEmpty();
+  }
+
+  private PersistDuplicationDataStep underTest() {
+    return new PersistDuplicationDataStep(db.getDbClient(), treeRootHolder, metricRepository, duplicationRepository,
+      new MeasureToMeasureDto(analysisMetadataHolder, treeRootHolder));
+  }
+
+  private void assertThatNothingPersisted() {
+    assertThat(db.countRowsOfTable(db.getSession(), "live_measures")).isEqualTo(0);
+  }
+
+  private Optional<String> selectMeasureData(String componentUuid) {
+      return db.getDbClient().liveMeasureDao().selectMeasure(db.getSession(), componentUuid, "duplications_data")
+      .map(LiveMeasureDto::getTextValue);
+  }
+
+  private ComponentDto insertComponent(String key, String uuid) {
+    ComponentDto componentDto = new ComponentDto()
+      .setOrganizationUuid("org1")
+      .setDbKey(key)
+      .setUuid(uuid)
+      .setUuidPath(uuid + ".")
+      .setRootUuid(uuid)
+      .setProjectUuid(uuid);
+    db.getDbClient().componentDao().insert(db.getSession(), componentDto);
+    return componentDto;
+  }
+
+  private static void verifyStatistics(TestComputationStepContext context, int expectedInsertsOrUpdates) {
+    context.getStatistics().assertValue("insertsOrUpdates", expectedInsertsOrUpdates);
+  }
+}