fix flaky tests in SegmentReplicationPressureIT (#6868)

Signed-off-by: Poojita Raj <poojiraj@amazon.com>
(cherry picked from commit 7b708c4)
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

server/src/internalClusterTest/java/org/opensearch/index/SegmentReplicationPressureIT.java

@@ -17,6 +17,7 @@
 import org.opensearch.common.util.concurrent.OpenSearchRejectedExecutionException;
 import org.opensearch.index.shard.IndexShard;
 import org.opensearch.indices.replication.SegmentReplicationBaseIT;
+import org.opensearch.indices.replication.common.ReplicationType;
 import org.opensearch.plugins.Plugin;
 import org.opensearch.rest.RestStatus;
 import org.opensearch.test.OpenSearchIntegTestCase;
@@ -52,12 +53,24 @@ protected Settings nodeSettings(int nodeOrdinal) {
             .build();
     }
 
+    @Override
+    public Settings indexSettings() {
+        // we want to control refreshes
+        return Settings.builder()
+            .put(super.indexSettings())
+            .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, SHARD_COUNT)
+            .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, REPLICA_COUNT)
+            .put(IndexModule.INDEX_QUERY_CACHE_ENABLED_SETTING.getKey(), false)
+            .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+            .put("index.refresh_interval", -1)
+            .build();
+    }
+
     @Override
     protected Collection<Class<? extends Plugin>> nodePlugins() {
         return asList(MockTransportService.TestPlugin.class);
     }
 
-    @AwaitsFix(bugUrl = "https://github.com/opensearch-project/OpenSearch/issues/6671")
     public void testWritesRejected() throws Exception {
         final String primaryNode = internalCluster().startNode();
         createIndex(INDEX_NAME);
@@ -76,6 +89,10 @@ public void testWritesRejected() throws Exception {
             indexingThread.start();
             indexingThread.join();
             latch.await();
+
+            indexDoc();
+            totalDocs.incrementAndGet();
+            refresh(INDEX_NAME);
             // index again while we are stale.
             assertBusy(() -> {
                 expectThrows(OpenSearchRejectedExecutionException.class, () -> {
@@ -90,6 +107,7 @@ public void testWritesRejected() throws Exception {
 
         // index another doc showing there is no pressure enforced.
         indexDoc();
+        refresh(INDEX_NAME);
         waitForSearchableDocs(totalDocs.incrementAndGet(), replicaNodes.toArray(new String[] {}));
         verifyStoreContent();
     }
@@ -98,7 +116,6 @@ public void testWritesRejected() throws Exception {
      * This test ensures that a replica can be added while the index is under write block.
      * Ensuring that only write requests are blocked.
      */
-    @AwaitsFix(bugUrl = "https://github.com/opensearch-project/OpenSearch/issues/6671")
     public void testAddReplicaWhileWritesBlocked() throws Exception {
         final String primaryNode = internalCluster().startNode();
         createIndex(INDEX_NAME);
@@ -118,6 +135,9 @@ public void testAddReplicaWhileWritesBlocked() throws Exception {
             indexingThread.start();
             indexingThread.join();
             latch.await();
+            indexDoc();
+            totalDocs.incrementAndGet();
+            refresh(INDEX_NAME);
             // index again while we are stale.
             assertBusy(() -> {
                 expectThrows(OpenSearchRejectedExecutionException.class, () -> {
@@ -142,6 +162,7 @@ public void testAddReplicaWhileWritesBlocked() throws Exception {
 
         // index another doc showing there is no pressure enforced.
         indexDoc();
+        refresh(INDEX_NAME);
         waitForSearchableDocs(totalDocs.incrementAndGet(), replicaNodes.toArray(new String[] {}));
         verifyStoreContent();
     }
@@ -258,7 +279,7 @@ private void assertFailedRequests(BulkResponse response) {
     }
 
     private void indexDoc() {
-        client().prepareIndex(INDEX_NAME).setId(UUIDs.base64UUID()).setSource("{}", "{}").get();
+        client().prepareIndex(INDEX_NAME).setId(UUIDs.base64UUID()).setSource("{}", "{}").execute().actionGet();
     }
 
     private void assertEqualSegmentInfosVersion(List<String> replicaNames, IndexShard primaryShard) {