diff --git a/sonar-scanner-engine/src/main/java/org/sonar/scanner/scan/filesystem/ProjectFilePreprocessor.java b/sonar-scanner-engine/src/main/java/org/sonar/scanner/scan/filesystem/ProjectFilePreprocessor.java
index 40d604fb0825..0633bcc8f72c 100644
--- a/sonar-scanner-engine/src/main/java/org/sonar/scanner/scan/filesystem/ProjectFilePreprocessor.java
+++ b/sonar-scanner-engine/src/main/java/org/sonar/scanner/scan/filesystem/ProjectFilePreprocessor.java
@@ -72,6 +72,8 @@ public class ProjectFilePreprocessor {
   private final Map<DefaultInputModule, List<Path>> mainSourcesByModule = new HashMap<>();
   private final Map<DefaultInputModule, List<Path>> testSourcesByModule = new HashMap<>();
 
+  private final ProgressReport progressReport = new ProgressReport("Report about progress of file preprocessing",
+    TimeUnit.SECONDS.toMillis(10));
   private int totalFilesPreprocessed = 0;
 
   public ProjectFilePreprocessor(AnalysisWarnings analysisWarnings, ScmConfiguration scmConfiguration, InputModuleHierarchy inputModuleHierarchy,
@@ -93,9 +95,8 @@ public ProjectFilePreprocessor(AnalysisWarnings analysisWarnings, ScmConfigurati
   }
 
   public void execute() {
-    ProgressReport progressReport = new ProgressReport("Report about progress of file preprocessing",
-      TimeUnit.SECONDS.toMillis(10));
     progressReport.start("Preprocessing files...");
+    progressReport.message(() -> String.format("Preprocessed %s files", totalFilesPreprocessed));
     ExclusionCounter exclusionCounter = new ExclusionCounter();
 
     if (useScmExclusion) {
diff --git a/sonar-scanner-engine/src/main/java/org/sonar/scanner/util/ProgressReport.java b/sonar-scanner-engine/src/main/java/org/sonar/scanner/util/ProgressReport.java
index 13c8f68afaf3..bb2e6481fe9a 100644
--- a/sonar-scanner-engine/src/main/java/org/sonar/scanner/util/ProgressReport.java
+++ b/sonar-scanner-engine/src/main/java/org/sonar/scanner/util/ProgressReport.java
@@ -19,6 +19,7 @@
  */
 package org.sonar.scanner.util;
 
+import java.util.function.Supplier;
 import javax.annotation.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -28,7 +29,7 @@ public class ProgressReport implements Runnable {
   private static final Logger LOG = LoggerFactory.getLogger(ProgressReport.class);
   private final long period;
   private long startTime;
-  private String message = "";
+  private Supplier<String> messageSupplier = () -> "";
   private final Thread thread;
   private String stopMessage = null;
 
@@ -44,7 +45,7 @@ public void run() {
     while (!Thread.interrupted()) {
       try {
         Thread.sleep(period);
-        log(message);
+        log(messageSupplier.get());
       } catch (InterruptedException e) {
         break;
       }
@@ -61,7 +62,11 @@ public void start(String startMessage) {
   }
 
   public void message(String message) {
-    this.message = message;
+    this.message(() -> message);
+  }
+
+  public void message(Supplier<String> messageSupplier) {
+    this.messageSupplier = messageSupplier;
   }
 
   public void stop(@Nullable String stopMessage) {
diff --git a/sonar-scanner-engine/src/test/java/org/sonar/scanner/util/ProgressReportTest.java b/sonar-scanner-engine/src/test/java/org/sonar/scanner/util/ProgressReportTest.java
index 71a3fd644a12..cf44ce6cf82f 100644
--- a/sonar-scanner-engine/src/test/java/org/sonar/scanner/util/ProgressReportTest.java
+++ b/sonar-scanner-engine/src/test/java/org/sonar/scanner/util/ProgressReportTest.java
@@ -42,7 +42,7 @@ public class ProgressReportTest {
   @Rule
   public LogTester logTester = new LogTester();
 
-  private ProgressReport underTest = new ProgressReport(THREAD_NAME, 1);
+  private final ProgressReport underTest = new ProgressReport(THREAD_NAME, 1);
 
   @Test
   public void stop_thread_on_stop() {
@@ -66,15 +66,28 @@ public void do_log() {
     underTest.message("Some message");
     boolean logged = false;
     while (!logged) {
-      logged = containsWithRetry("Some message");
+      logged = waitForMessageStartingWith("Some message");
     }
     underTest.stop("stop");
-    assertThat(containsWithRetry("stop")).isTrue();
+    assertThat(waitForMessageStartingWith("stop")).isTrue();
   }
 
-  private boolean containsWithRetry(String message) {
+  @Test
+  public void do_log_message_supplier() {
+    logTester.setLevel(Level.DEBUG);
+    underTest.start("start");
+    underTest.message(() -> "Some message " + System.currentTimeMillis());
+    boolean logged = false;
+    while (!logged) {
+      logged = waitForMessageStartingWith("Some message ");
+    }
+    underTest.stop("stop");
+    assertThat(waitForMessageStartingWith("stop")).isTrue();
+  }
+
+  private boolean waitForMessageStartingWith(String message) {
     try {
-      Awaitility.await().atMost(5, TimeUnit.SECONDS).until(() -> logTester.logs().contains(message));
+      Awaitility.await().atMost(5, TimeUnit.SECONDS).until(() -> logTester.logs().stream().anyMatch(s -> s.startsWith(message)));
     } catch (ConditionTimeoutException e) {
       return false;
     }