diff --git a/java/execution/impl/src/com/intellij/execution/testframework/SearchForTestsTask.java b/java/execution/impl/src/com/intellij/execution/testframework/SearchForTestsTask.java
index 58288410c8bf..536ced5df441 100644
--- a/java/execution/impl/src/com/intellij/execution/testframework/SearchForTestsTask.java
+++ b/java/execution/impl/src/com/intellij/execution/testframework/SearchForTestsTask.java
@@ -31,6 +31,7 @@ import com.intellij.openapi.progress.impl.BackgroundableProcessIndicator;
 import com.intellij.openapi.progress.util.ProgressIndicatorUtils;
 import com.intellij.openapi.project.DumbService;
 import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.registry.Registry;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -112,8 +113,13 @@ public abstract class SearchForTestsTask extends Task.Backgroundable {
           ex[0] = e;
         }
       };
-      //noinspection StatementWithEmptyBody
-      while (!runSmartModeReadActionWithWritePriority(runnable, new SensitiveProgressWrapper(indicator)));
+      if (Registry.is("junit4.search.4.tests.in.classpath", false)) {
+        runnable.run();
+      }
+      else {
+        //noinspection StatementWithEmptyBody
+        while (!runSmartModeReadActionWithWritePriority(runnable, new SensitiveProgressWrapper(indicator)));
+      }
       if (ex[0] != null) {
         logCantRunException(ex[0]);
       }
@@ -169,7 +175,7 @@ public abstract class SearchForTestsTask extends Task.Backgroundable {
 
   @Override
   public void onSuccess() {
-    DumbService.getInstance(getProject()).runWhenSmart(() -> {
+    Runnable runnable = () -> {
       try {
         onFound();
       }
@@ -177,7 +183,13 @@ public abstract class SearchForTestsTask extends Task.Backgroundable {
         LOG.error(e);
       }
       finish();
-    });
+    };
+    if (Registry.is("junit4.search.4.tests.in.classpath", false)) {
+      runnable.run();
+    }
+    else {
+      DumbService.getInstance(getProject()).runWhenSmart(runnable);
+    }
   }
 
   public void finish() {
diff --git a/plugins/junit/src/com/intellij/execution/junit/TestPackage.java b/plugins/junit/src/com/intellij/execution/junit/TestPackage.java
index 17e5c5797c75..dbab469fcbdf 100644
--- a/plugins/junit/src/com/intellij/execution/junit/TestPackage.java
+++ b/plugins/junit/src/com/intellij/execution/junit/TestPackage.java
@@ -26,6 +26,7 @@ import com.intellij.execution.testframework.SourceScope;
 import com.intellij.execution.testframework.TestSearchScope;
 import com.intellij.openapi.application.ReadAction;
 import com.intellij.openapi.module.Module;
+import com.intellij.openapi.project.DumbService;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.Comparing;
 import com.intellij.openapi.util.Ref;
@@ -71,7 +72,9 @@ public class TestPackage extends TestObject {
         final SourceScope sourceScope = getSourceScope();
         final Module module = getConfiguration().getConfigurationModule().getModule();
         if (sourceScope != null && !ReadAction.compute(() -> isJUnit5(module, sourceScope, myProject))) {
+          DumbService instance = DumbService.getInstance(myProject);
           try {
+            instance.setAlternativeResolveEnabled(true);
             final TestClassFilter classFilter = getClassFilter(data);
             LOG.assertTrue(classFilter.getBase() != null);
             long start = System.currentTimeMillis();
@@ -81,7 +84,7 @@ public class TestPackage extends TestObject {
               PsiManager manager = PsiManager.getInstance(myProject);
               Arrays.stream(classNames)
                 .filter(className -> acceptClassName(className)) //check patterns
-                .map(name -> ClassUtil.findPsiClass(manager, name, null, true, classFilter.getScope()))
+                .map(name -> ReadAction.compute(() -> ClassUtil.findPsiClass(manager, name, null, true, classFilter.getScope())))
                 .filter(aClass -> aClass != null)
                 .forEach(myClasses::add);
               LOG.info("Found tests in " + (System.currentTimeMillis() - start));
@@ -91,6 +94,9 @@ public class TestPackage extends TestObject {
             }
           }
           catch (CantRunException ignored) {}
+          finally {
+            instance.setAlternativeResolveEnabled(false);
+          }
         }
       }