Revert Enabling Segment Replication Backpressure setting by default (opensearch-project#7292)

* Revert "[Segment Replication] Enable Segment Replication Backpressure setting by default. (opensearch-project#7183)"

This reverts commit a953178.

* Add null checks.

Signed-off-by: Rishikesh1159 <rishireddy1159@gmail.com>

* add testWithDocumentReplicationEnabledIndex().

Signed-off-by: Rishikesh1159 <rishireddy1159@gmail.com>

---------

Signed-off-by: Rishikesh1159 <rishireddy1159@gmail.com>

Author: Rishikesh1159

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

@@ -38,6 +38,7 @@
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_NUMBER_OF_REPLICAS;
 import static org.opensearch.index.SegmentReplicationPressureService.MAX_INDEXING_CHECKPOINTS;
 import static org.opensearch.index.SegmentReplicationPressureService.MAX_REPLICATION_TIME_SETTING;
+import static org.opensearch.index.SegmentReplicationPressureService.SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertHitCount;
 
@@ -50,6 +51,7 @@ public class SegmentReplicationPressureIT extends SegmentReplicationBaseIT {
     protected Settings nodeSettings(int nodeOrdinal) {
         return Settings.builder()
             .put(super.nodeSettings(nodeOrdinal))
+            .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
             .put(MAX_REPLICATION_TIME_SETTING.getKey(), TimeValue.timeValueSeconds(1))
             .put(MAX_INDEXING_CHECKPOINTS.getKey(), MAX_CHECKPOINTS_BEHIND)
             .build();

server/src/main/java/org/opensearch/index/SegmentReplicationPressureService.java

@@ -52,7 +52,7 @@ public class SegmentReplicationPressureService implements Closeable {
      */
     public static final Setting<Boolean> SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED = Setting.boolSetting(
         "segrep.pressure.enabled",
-        true,
+        false,
         Setting.Property.Dynamic,
         Setting.Property.NodeScope
     );

server/src/test/java/org/opensearch/index/SegmentReplicationPressureServiceTests.java

@@ -41,12 +41,14 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.times;
 import static org.opensearch.index.SegmentReplicationPressureService.MAX_REPLICATION_TIME_SETTING;
+import static org.opensearch.index.SegmentReplicationPressureService.SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED;
 
 public class SegmentReplicationPressureServiceTests extends OpenSearchIndexLevelReplicationTestCase {
 
     private static ShardStateAction shardStateAction = Mockito.mock(ShardStateAction.class);
     private static final Settings settings = Settings.builder()
         .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+        .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
         .put(MAX_REPLICATION_TIME_SETTING.getKey(), TimeValue.timeValueSeconds(5))
         .build();
 
@@ -97,7 +99,10 @@ public void testIsSegrepLimitBreached() throws Exception {
     }
 
     public void testIsSegrepLimitBreached_onlyCheckpointLimitBreached() throws Exception {
-        final Settings settings = Settings.builder().put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT).build();
+        final Settings settings = Settings.builder()
+            .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+            .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
+            .build();
 
         try (ReplicationGroup shards = createGroup(1, settings, new NRTReplicationEngineFactory())) {
             shards.startAll();
@@ -121,7 +126,10 @@ public void testIsSegrepLimitBreached_onlyCheckpointLimitBreached() throws Excep
     }
 
     public void testIsSegrepLimitBreached_onlyTimeLimitBreached() throws Exception {
-        final Settings settings = Settings.builder().put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT).build();
+        final Settings settings = Settings.builder()
+            .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+            .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
+            .build();
 
         try (ReplicationGroup shards = createGroup(1, settings, new NRTReplicationEngineFactory())) {
             shards.startAll();
@@ -186,6 +194,7 @@ public void testIsSegrepLimitBreached_underStaleNodeLimit() throws Exception {
     public void testFailStaleReplicaTask() throws Exception {
         final Settings settings = Settings.builder()
             .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+            .put(SEGMENT_REPLICATION_INDEXING_PRESSURE_ENABLED.getKey(), true)
             .put(MAX_REPLICATION_TIME_SETTING.getKey(), TimeValue.timeValueMillis(10))
             .build();