diff --git a/server/src/test/java/org/opensearch/lucene/index/ShuffleForcedMergePolicyTests.java b/server/src/test/java/org/opensearch/lucene/index/ShuffleForcedMergePolicyTests.java
index e583c12473a30..8842b7db5c6b4 100644
--- a/server/src/test/java/org/opensearch/lucene/index/ShuffleForcedMergePolicyTests.java
+++ b/server/src/test/java/org/opensearch/lucene/index/ShuffleForcedMergePolicyTests.java
@@ -58,7 +58,7 @@
 public class ShuffleForcedMergePolicyTests extends BaseMergePolicyTestCase {
     public void testDiagnostics() throws IOException {
         try (Directory dir = newDirectory()) {
-            IndexWriterConfig iwc = newIndexWriterConfig();
+            IndexWriterConfig iwc = newIndexWriterConfig().setMaxFullFlushMergeWaitMillis(0);
             MergePolicy mp = new ShuffleForcedMergePolicy(newTieredMergePolicy());
             iwc.setMergePolicy(mp);
             boolean sorted = random().nextBoolean();