diff --git a/contrib/pax_storage/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out b/contrib/pax_storage/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out
index ae21059fcb6..1e011ecec22 100644
--- a/contrib/pax_storage/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out
+++ b/contrib/pax_storage/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out
@@ -33,8 +33,8 @@ CREATE
 -- verify_cpu_usage: calculate each QE's average cpu usage using all the data in
 -- the table cpu_usage_sample. And compare the average value to the expected value.
 -- return true if the practical value is close to the expected value.
-CREATE OR REPLACE FUNCTION verify_cpu_usage(groupname TEXT, expect_cpu_usage INT, err_rate INT) RETURNS BOOL AS $$ import json import functools 
-all_info = plpy.execute(''' SELECT sample::json->'{name}' AS cpu FROM cpu_usage_samples '''.format(name=groupname)) usage = float(all_info[0]['cpu']) 
+CREATE OR REPLACE FUNCTION verify_cpu_usage(groupname TEXT, expect_cpu_usage INT, err_rate INT) RETURNS BOOL AS $$ import json 
+all_info = plpy.execute(''' SELECT sample::json->'{name}' AS cpu FROM cpu_usage_samples '''.format(name=groupname)) usage = sum(float(row['cpu']) for row in all_info) / len(all_info) 
 return abs(usage - expect_cpu_usage) <= err_rate $$ LANGUAGE plpython3u;
 CREATE
 
diff --git a/contrib/pax_storage/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql b/contrib/pax_storage/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql
index 14220c38a42..a014108bb52 100644
--- a/contrib/pax_storage/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql
+++ b/contrib/pax_storage/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql
@@ -38,12 +38,11 @@ $$ LANGUAGE plpython3u;
 CREATE OR REPLACE FUNCTION verify_cpu_usage(groupname TEXT, expect_cpu_usage INT, err_rate INT)
 RETURNS BOOL AS $$
     import json
-    import functools
 
     all_info = plpy.execute('''
         SELECT sample::json->'{name}' AS cpu FROM cpu_usage_samples
     '''.format(name=groupname))
-    usage = float(all_info[0]['cpu'])
+    usage = sum(float(row['cpu']) for row in all_info) / len(all_info)
 
     return abs(usage - expect_cpu_usage) <= err_rate
 $$ LANGUAGE plpython3u;
diff --git a/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy.out b/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy.out
index be070815b61..1f4d55e0b8a 100644
--- a/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy.out
+++ b/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy.out
@@ -1,3 +1,7 @@
+-- start_matchsubs
+-- m/\(cluster.c:\d+\)/
+-- s/\(cluster.c:\d+\)/\(cluster.c:###\)/
+-- end_matchsubs
 -- ALTER TABLE ... SET DISTRIBUTED BY
 -- This is the main interface for system expansion
 \set DATA values(1, 2), (2, 3), (3, 4)
@@ -171,7 +175,7 @@ ERROR:  permission denied: "pg_class" is a system catalog
 create table atsdb (i int, j text) distributed by (j);
 insert into atsdb select i, i::text from generate_series(1, 10) i;
 alter table atsdb set with(appendonly = true);
-ERROR:  PAX not allow swap relation files for different AM (cluster.c:1535)
+ERROR:  PAX not allow swap relation files for different AM (cluster.c:###)
 select relname, segrelid != 0, reloptions from pg_class, pg_appendonly where pg_class.oid =
 'atsdb'::regclass and relid = pg_class.oid;
  relname | ?column? | reloptions 
@@ -316,7 +320,7 @@ select * from distcheck where rel = 'atsdb';
 
 alter table atsdb drop column n;
 alter table atsdb set with(appendonly = true, compresslevel = 3);
-ERROR:  PAX not allow swap relation files for different AM (cluster.c:1535)
+ERROR:  PAX not allow swap relation files for different AM (cluster.c:###)
 select relname, segrelid != 0, reloptions from pg_class, pg_appendonly where pg_class.oid =
 'atsdb'::regclass and relid = pg_class.oid;
  relname | ?column? | reloptions 
diff --git a/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy_optimizer.out b/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy_optimizer.out
index df30a5d8f05..0eafd5f8854 100644
--- a/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy_optimizer.out
+++ b/contrib/pax_storage/src/test/regress/expected/alter_distribution_policy_optimizer.out
@@ -1,3 +1,7 @@
+-- start_matchsubs
+-- m/\(cluster.c:\d+\)/
+-- s/\(cluster.c:\d+\)/\(cluster.c:###\)/
+-- end_matchsubs
 -- ALTER TABLE ... SET DISTRIBUTED BY
 -- This is the main interface for system expansion
 \set DATA values(1, 2), (2, 3), (3, 4)
@@ -171,7 +175,7 @@ ERROR:  permission denied: "pg_class" is a system catalog
 create table atsdb (i int, j text) distributed by (j);
 insert into atsdb select i, i::text from generate_series(1, 10) i;
 alter table atsdb set with(appendonly = true);
-ERROR:  PAX not allow swap relation files for different AM (cluster.c:1535)
+ERROR:  PAX not allow swap relation files for different AM (cluster.c:###)
 select relname, segrelid != 0, reloptions from pg_class, pg_appendonly where pg_class.oid =
 'atsdb'::regclass and relid = pg_class.oid;
  relname | ?column? | reloptions 
@@ -316,7 +320,7 @@ select * from distcheck where rel = 'atsdb';
 
 alter table atsdb drop column n;
 alter table atsdb set with(appendonly = true, compresslevel = 3);
-ERROR:  PAX not allow swap relation files for different AM (cluster.c:1535)
+ERROR:  PAX not allow swap relation files for different AM (cluster.c:###)
 select relname, segrelid != 0, reloptions from pg_class, pg_appendonly where pg_class.oid =
 'atsdb'::regclass and relid = pg_class.oid;
  relname | ?column? | reloptions 
diff --git a/contrib/pax_storage/src/test/regress/expected/rowtypes.out b/contrib/pax_storage/src/test/regress/expected/rowtypes.out
index 9c92b2c403d..076f5cbb606 100644
--- a/contrib/pax_storage/src/test/regress/expected/rowtypes.out
+++ b/contrib/pax_storage/src/test/regress/expected/rowtypes.out
@@ -70,41 +70,36 @@ LINE 1: select '(Joe,Blow) /'::fullname;
                ^
 DETAIL:  Junk after right parenthesis.
 -- test non-error-throwing API
--- MERGE16_FIXME: 
--- The greenplum implement complex type by itself, postgres implement
--- it now. should we use the complex type implemented by postgres.
--- start_ignore
-SELECT pg_input_is_valid('(1,2)', 'complex');
+SELECT pg_input_is_valid('(1,2)', 'complex_t');
  pg_input_is_valid 
 -------------------
  t
 (1 row)
 
-SELECT pg_input_is_valid('(1,2', 'complex');
+SELECT pg_input_is_valid('(1,2', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT pg_input_is_valid('(1,zed)', 'complex');
+SELECT pg_input_is_valid('(1,zed)', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,zed)', 'complex');
+SELECT * FROM pg_input_error_info('(1,zed)', 'complex_t');
                         message                        | detail | hint | sql_error_code 
 -------------------------------------------------------+--------+------+----------------
  invalid input syntax for type double precision: "zed" |        |      | 22P02
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,1e400)', 'complex');
+SELECT * FROM pg_input_error_info('(1,1e400)', 'complex_t');
                       message                      | detail | hint | sql_error_code 
 ---------------------------------------------------+--------+------+----------------
  "1e400" is out of range for type double precision |        |      | 22003
 (1 row)
 
--- end_ignore
 create temp table quadtable(f1 int, q quad);
 insert into quadtable values (1, ((3.3,4.4),(5.5,6.6)));
 insert into quadtable values (2, ((null,4.4),(5.5,6.6)));
diff --git a/contrib/pax_storage/src/test/regress/expected/rowtypes_optimizer.out b/contrib/pax_storage/src/test/regress/expected/rowtypes_optimizer.out
index 32d93a68e4d..f0a84ed44d4 100644
--- a/contrib/pax_storage/src/test/regress/expected/rowtypes_optimizer.out
+++ b/contrib/pax_storage/src/test/regress/expected/rowtypes_optimizer.out
@@ -70,41 +70,36 @@ LINE 1: select '(Joe,Blow) /'::fullname;
                ^
 DETAIL:  Junk after right parenthesis.
 -- test non-error-throwing API
--- MERGE16_FIXME: 
--- The greenplum implement complex type by itself, postgres implement
--- it now. should we use the complex type implemented by postgres.
--- start_ignore
-SELECT pg_input_is_valid('(1,2)', 'complex');
+SELECT pg_input_is_valid('(1,2)', 'complex_t');
  pg_input_is_valid 
 -------------------
  t
 (1 row)
 
-SELECT pg_input_is_valid('(1,2', 'complex');
+SELECT pg_input_is_valid('(1,2', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT pg_input_is_valid('(1,zed)', 'complex');
+SELECT pg_input_is_valid('(1,zed)', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,zed)', 'complex');
+SELECT * FROM pg_input_error_info('(1,zed)', 'complex_t');
                         message                        | detail | hint | sql_error_code 
 -------------------------------------------------------+--------+------+----------------
  invalid input syntax for type double precision: "zed" |        |      | 22P02
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,1e400)', 'complex');
+SELECT * FROM pg_input_error_info('(1,1e400)', 'complex_t');
                       message                      | detail | hint | sql_error_code 
 ---------------------------------------------------+--------+------+----------------
  "1e400" is out of range for type double precision |        |      | 22003
 (1 row)
 
--- end_ignore
 create temp table quadtable(f1 int, q quad);
 insert into quadtable values (1, ((3.3,4.4),(5.5,6.6)));
 insert into quadtable values (2, ((null,4.4),(5.5,6.6)));
diff --git a/contrib/pax_storage/src/test/regress/sql/alter_distribution_policy.sql b/contrib/pax_storage/src/test/regress/sql/alter_distribution_policy.sql
index feade3ed93d..6345ae987ec 100644
--- a/contrib/pax_storage/src/test/regress/sql/alter_distribution_policy.sql
+++ b/contrib/pax_storage/src/test/regress/sql/alter_distribution_policy.sql
@@ -1,3 +1,7 @@
+-- start_matchsubs
+-- m/\(cluster.c:\d+\)/
+-- s/\(cluster.c:\d+\)/\(cluster.c:###\)/
+-- end_matchsubs
 -- ALTER TABLE ... SET DISTRIBUTED BY
 -- This is the main interface for system expansion
 \set DATA values(1, 2), (2, 3), (3, 4)
diff --git a/contrib/pax_storage/src/test/regress/sql/rowtypes.sql b/contrib/pax_storage/src/test/regress/sql/rowtypes.sql
index 7db4925dbe8..93319bf7e81 100644
--- a/contrib/pax_storage/src/test/regress/sql/rowtypes.sql
+++ b/contrib/pax_storage/src/test/regress/sql/rowtypes.sql
@@ -42,16 +42,11 @@ select ' (Joe,Blow)  '::fullname;  -- ok, extra whitespace
 select '(Joe,Blow) /'::fullname;  -- bad
 
 -- test non-error-throwing API
--- MERGE16_FIXME: 
--- The greenplum implement complex type by itself, postgres implement
--- it now. should we use the complex type implemented by postgres.
--- start_ignore
-SELECT pg_input_is_valid('(1,2)', 'complex');
-SELECT pg_input_is_valid('(1,2', 'complex');
-SELECT pg_input_is_valid('(1,zed)', 'complex');
-SELECT * FROM pg_input_error_info('(1,zed)', 'complex');
-SELECT * FROM pg_input_error_info('(1,1e400)', 'complex');
--- end_ignore
+SELECT pg_input_is_valid('(1,2)', 'complex_t');
+SELECT pg_input_is_valid('(1,2', 'complex_t');
+SELECT pg_input_is_valid('(1,zed)', 'complex_t');
+SELECT * FROM pg_input_error_info('(1,zed)', 'complex_t');
+SELECT * FROM pg_input_error_info('(1,1e400)', 'complex_t');
 
 create temp table quadtable(f1 int, q quad);
 
diff --git a/src/backend/access/aocs/aocsam_handler.c b/src/backend/access/aocs/aocsam_handler.c
index 5cbf2015c64..4dc7d541c5f 100644
--- a/src/backend/access/aocs/aocsam_handler.c
+++ b/src/backend/access/aocs/aocsam_handler.c
@@ -1462,8 +1462,6 @@ aoco_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
 	int			natts;
 	Datum	   *values;
 	bool	   *isnull;
-	TransactionId FreezeXid;
-	MultiXactId MultiXactCutoff;
 	Tuplesortstate *tuplesort;
 	PGRUsage	ru0;
 
@@ -1523,29 +1521,12 @@ aoco_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
 	Assert(RelationGetTargetBlock(NewHeap) == InvalidBlockNumber);
 
 	/*
-	 * Compute sane values for FreezeXid and CutoffMulti with regular
-	 * VACUUM machinery to avoidconfising existing CLUSTER code.
+	 * AO/AOCO tables have no per-tuple xmin/xmax, so freeze limits don't
+	 * apply. Return Invalid values so that relfrozenxid and relminmxid
+	 * remain unchanged after CLUSTER.
 	 */
-	vacuum_set_xid_limits(OldHeap, 0, 0, 0, 0,
-						  &OldestXmin, &FreezeXid, NULL, &MultiXactCutoff,
-						  NULL);
-
-	/*
-	 * FreezeXid will become the table's new relfrozenxid, and that mustn't go
-	 * backwards, so take the max.
-	 */
-	if (TransactionIdPrecedes(FreezeXid, OldHeap->rd_rel->relfrozenxid))
-		FreezeXid = OldHeap->rd_rel->relfrozenxid;
-
-	/*
-	 * MultiXactCutoff, similarly, shouldn't go backwards either.
-	 */
-	if (MultiXactIdPrecedes(MultiXactCutoff, OldHeap->rd_rel->relminmxid))
-		MultiXactCutoff = OldHeap->rd_rel->relminmxid;
-
-	/* return selected values to caller */
-	*xid_cutoff = FreezeXid;
-	*multi_cutoff = MultiXactCutoff;
+	*xid_cutoff = InvalidTransactionId;
+	*multi_cutoff = InvalidMultiXactId;
 
 	tuplesort = tuplesort_begin_cluster(oldTupDesc, OldIndex,
 											maintenance_work_mem, NULL, false);
diff --git a/src/backend/access/appendonly/appendonlyam_handler.c b/src/backend/access/appendonly/appendonlyam_handler.c
index cd37c0bbacd..cae12e110ff 100644
--- a/src/backend/access/appendonly/appendonlyam_handler.c
+++ b/src/backend/access/appendonly/appendonlyam_handler.c
@@ -1317,8 +1317,6 @@ appendonly_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
 	int			natts;
 	Datum	   *values;
 	bool	   *isnull;
-	TransactionId FreezeXid;
-	MultiXactId MultiXactCutoff;
 	Tuplesortstate *tuplesort;
 	PGRUsage	ru0;
 
@@ -1380,29 +1378,12 @@ appendonly_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
 	Assert(RelationGetTargetBlock(NewHeap) == InvalidBlockNumber);
 
 	/*
-	 * Compute sane values for FreezeXid and CutoffMulti with regular
-	 * VACUUM machinery to avoidconfising existing CLUSTER code.
+	 * AO/AOCO tables have no per-tuple xmin/xmax, so freeze limits don't
+	 * apply. Return Invalid values so that relfrozenxid and relminmxid
+	 * remain unchanged after CLUSTER.
 	 */
-	vacuum_set_xid_limits(OldHeap, 0, 0, 0, 0,
-						  &OldestXmin, &FreezeXid, NULL, &MultiXactCutoff,
-						  NULL);
-
-	/*
-	 * FreezeXid will become the table's new relfrozenxid, and that mustn't go
-	 * backwards, so take the max.
-	 */
-	if (TransactionIdPrecedes(FreezeXid, OldHeap->rd_rel->relfrozenxid))
-		FreezeXid = OldHeap->rd_rel->relfrozenxid;
-
-	/*
-	 * MultiXactCutoff, similarly, shouldn't go backwards either.
-	 */
-	if (MultiXactIdPrecedes(MultiXactCutoff, OldHeap->rd_rel->relminmxid))
-		MultiXactCutoff = OldHeap->rd_rel->relminmxid;
-
-	/* return selected values to caller */
-	*xid_cutoff = FreezeXid;
-	*multi_cutoff = MultiXactCutoff;
+	*xid_cutoff = InvalidTransactionId;
+	*multi_cutoff = InvalidMultiXactId;
 
 	tuplesort = tuplesort_begin_cluster(oldTupDesc, OldIndex,
 											maintenance_work_mem, NULL, false);
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index e31fe4cef8e..a3d2ad87bfb 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -1486,17 +1486,24 @@ swap_relation_files(Oid r1, Oid r2, bool target_is_pg_class,
 		Assert(!TransactionIdIsValid(frozenXid) ||
 			   TransactionIdIsNormal(frozenXid));
 		relform1->relfrozenxid = frozenXid;
-		Assert(MultiXactIdIsValid(cutoffMulti));
+		Assert(!MultiXactIdIsValid(cutoffMulti) ||
+			   MultiXactIdPrecedesOrEquals(FirstMultiXactId, cutoffMulti));
 		relform1->relminmxid = cutoffMulti;
 	}
 	/*
-	 * Cloudberry: append-optimized tables do not have a valid relfrozenxid.
-	 * Overwrite the entry for both relations.
+	 * Cloudberry: append-optimized tables do not have a valid relfrozenxid
+	 * or relminmxid. Overwrite the entry for both relations.
 	 */
 	if (relform1->relkind != RELKIND_INDEX && IsAccessMethodAO(relform1->relam))
+	{
 		relform1->relfrozenxid = InvalidTransactionId;
+		relform1->relminmxid = InvalidMultiXactId;
+	}
 	if (relform2->relkind != RELKIND_INDEX && IsAccessMethodAO(relform2->relam))
+	{
 		relform2->relfrozenxid = InvalidTransactionId;
+		relform2->relminmxid = InvalidMultiXactId;
+	}
 
 	/* swap size statistics too, since new rel has freshly-updated stats */
 	if (swap_stats)
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 80585a878a7..f4ba5615d5a 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -3914,202 +3914,3 @@ vac_cmp_itemptr(const void *left, const void *right)
 	return 0;
 }
 
-
-void
-vacuum_set_xid_limits(Relation rel,
-					  int freeze_min_age,
-					  int freeze_table_age,
-					  int multixact_freeze_min_age,
-					  int multixact_freeze_table_age,
-					  TransactionId *oldestXmin,
-					  TransactionId *freezeLimit,
-					  TransactionId *xidFullScanLimit,
-					  MultiXactId *multiXactCutoff,
-					  MultiXactId *mxactFullScanLimit)
-{
-	int			freezemin;
-	int			mxid_freezemin;
-	int			effective_multixact_freeze_max_age;
-	TransactionId limit;
-	TransactionId safeLimit;
-	MultiXactId oldestMxact;
-	MultiXactId mxactLimit;
-	MultiXactId safeMxactLimit;
-
-	/*
-	 * We can always ignore processes running lazy vacuum.  This is because we
-	 * use these values only for deciding which tuples we must keep in the
-	 * tables.  Since lazy vacuum doesn't write its XID anywhere (usually no
-	 * XID assigned), it's safe to ignore it.  In theory it could be
-	 * problematic to ignore lazy vacuums in a full vacuum, but keep in mind
-	 * that only one vacuum process can be working on a particular table at
-	 * any time, and that each vacuum is always an independent transaction.
-	 */
-	*oldestXmin = GetOldestNonRemovableTransactionId(rel);
-
-	if (OldSnapshotThresholdActive())
-	{
-		TransactionId limit_xmin;
-		TimestampTz limit_ts;
-
-		if (TransactionIdLimitedForOldSnapshots(*oldestXmin, rel,
-												&limit_xmin, &limit_ts))
-		{
-			/*
-			 * TODO: We should only set the threshold if we are pruning on the
-			 * basis of the increased limits.  Not as crucial here as it is
-			 * for opportunistic pruning (which often happens at a much higher
-			 * frequency), but would still be a significant improvement.
-			 */
-			SetOldSnapshotThresholdTimestamp(limit_ts, limit_xmin);
-			*oldestXmin = limit_xmin;
-		}
-	}
-
-	Assert(TransactionIdIsNormal(*oldestXmin));
-
-	/*
-	 * Determine the minimum freeze age to use: as specified by the caller, or
-	 * vacuum_freeze_min_age, but in any case not more than half
-	 * autovacuum_freeze_max_age, so that autovacuums to prevent XID
-	 * wraparound won't occur too frequently.
-	 */
-	freezemin = freeze_min_age;
-	if (freezemin < 0)
-		freezemin = vacuum_freeze_min_age;
-	freezemin = Min(freezemin, autovacuum_freeze_max_age / 2);
-	Assert(freezemin >= 0);
-
-	/*
-	 * Compute the cutoff XID, being careful not to generate a "permanent" XID
-	 */
-	limit = *oldestXmin - freezemin;
-	if (!TransactionIdIsNormal(limit))
-		limit = FirstNormalTransactionId;
-
-	/*
-	 * If oldestXmin is very far back (in practice, more than
-	 * autovacuum_freeze_max_age / 2 XIDs old), complain and force a minimum
-	 * freeze age of zero.
-	 */
-	safeLimit = ReadNextTransactionId() - autovacuum_freeze_max_age;
-	if (!TransactionIdIsNormal(safeLimit))
-		safeLimit = FirstNormalTransactionId;
-
-	if (TransactionIdPrecedes(limit, safeLimit))
-	{
-		ereport(WARNING,
-				(errmsg("oldest xmin is far in the past"),
-						errhint("Close open transactions soon to avoid wraparound problems.\n"
-								"You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-		limit = *oldestXmin;
-	}
-
-	*freezeLimit = limit;
-
-	/*
-	 * Compute the multixact age for which freezing is urgent.  This is
-	 * normally autovacuum_multixact_freeze_max_age, but may be less if we are
-	 * short of multixact member space.
-	 */
-	effective_multixact_freeze_max_age = MultiXactMemberFreezeThreshold();
-
-	/*
-	 * Determine the minimum multixact freeze age to use: as specified by
-	 * caller, or vacuum_multixact_freeze_min_age, but in any case not more
-	 * than half effective_multixact_freeze_max_age, so that autovacuums to
-	 * prevent MultiXact wraparound won't occur too frequently.
-	 */
-	mxid_freezemin = multixact_freeze_min_age;
-	if (mxid_freezemin < 0)
-		mxid_freezemin = vacuum_multixact_freeze_min_age;
-	mxid_freezemin = Min(mxid_freezemin,
-						 effective_multixact_freeze_max_age / 2);
-	Assert(mxid_freezemin >= 0);
-
-	/* compute the cutoff multi, being careful to generate a valid value */
-	oldestMxact = GetOldestMultiXactId();
-	mxactLimit = oldestMxact - mxid_freezemin;
-	if (mxactLimit < FirstMultiXactId)
-		mxactLimit = FirstMultiXactId;
-
-	safeMxactLimit =
-			ReadNextMultiXactId() - effective_multixact_freeze_max_age;
-	if (safeMxactLimit < FirstMultiXactId)
-		safeMxactLimit = FirstMultiXactId;
-
-	if (MultiXactIdPrecedes(mxactLimit, safeMxactLimit))
-	{
-		ereport(WARNING,
-				(errmsg("oldest multixact is far in the past"),
-						errhint("Close open transactions with multixacts soon to avoid wraparound problems.")));
-		/* Use the safe limit, unless an older mxact is still running */
-		if (MultiXactIdPrecedes(oldestMxact, safeMxactLimit))
-			mxactLimit = oldestMxact;
-		else
-			mxactLimit = safeMxactLimit;
-	}
-
-	*multiXactCutoff = mxactLimit;
-
-	if (xidFullScanLimit != NULL)
-	{
-		int			freezetable;
-
-		Assert(mxactFullScanLimit != NULL);
-
-		/*
-		 * Determine the table freeze age to use: as specified by the caller,
-		 * or vacuum_freeze_table_age, but in any case not more than
-		 * autovacuum_freeze_max_age * 0.95, so that if you have e.g nightly
-		 * VACUUM schedule, the nightly VACUUM gets a chance to freeze tuples
-		 * before anti-wraparound autovacuum is launched.
-		 */
-		freezetable = freeze_table_age;
-		if (freezetable < 0)
-			freezetable = vacuum_freeze_table_age;
-		freezetable = Min(freezetable, autovacuum_freeze_max_age * 0.95);
-		Assert(freezetable >= 0);
-
-		/*
-		 * Compute XID limit causing a full-table vacuum, being careful not to
-		 * generate a "permanent" XID.
-		 */
-		limit = ReadNextTransactionId() - freezetable;
-		if (!TransactionIdIsNormal(limit))
-			limit = FirstNormalTransactionId;
-
-		*xidFullScanLimit = limit;
-
-		/*
-		 * Similar to the above, determine the table freeze age to use for
-		 * multixacts: as specified by the caller, or
-		 * vacuum_multixact_freeze_table_age, but in any case not more than
-		 * autovacuum_multixact_freeze_table_age * 0.95, so that if you have
-		 * e.g. nightly VACUUM schedule, the nightly VACUUM gets a chance to
-		 * freeze multixacts before anti-wraparound autovacuum is launched.
-		 */
-		freezetable = multixact_freeze_table_age;
-		if (freezetable < 0)
-			freezetable = vacuum_multixact_freeze_table_age;
-		freezetable = Min(freezetable,
-						  effective_multixact_freeze_max_age * 0.95);
-		Assert(freezetable >= 0);
-
-		/*
-		 * Compute MultiXact limit causing a full-table vacuum, being careful
-		 * to generate a valid MultiXact value.
-		 */
-		mxactLimit = ReadNextMultiXactId() - freezetable;
-		if (mxactLimit < FirstMultiXactId)
-			mxactLimit = FirstMultiXactId;
-
-		*mxactFullScanLimit = mxactLimit;
-	}
-	else
-	{
-		Assert(mxactFullScanLimit == NULL);
-	}
-}
-
-
diff --git a/src/backend/commands/vacuum_ao.c b/src/backend/commands/vacuum_ao.c
index dd0522f1986..075c73fb1c1 100644
--- a/src/backend/commands/vacuum_ao.c
+++ b/src/backend/commands/vacuum_ao.c
@@ -245,11 +245,6 @@ ao_vacuum_rel_post_cleanup(Relation onerel, VacuumParams *params, BufferAccessSt
 	BlockNumber	total_file_segs;
 	int			elevel;
 	int			options = params->options;
-	TransactionId OldestXmin;
-	TransactionId FreezeLimit;
-	MultiXactId MultiXactCutoff;
-	TransactionId xidFullScanLimit;
-	MultiXactId mxactFullScanLimit;
 
 	if (options & VACOPT_VERBOSE)
 		elevel = INFO;
@@ -288,16 +283,11 @@ ao_vacuum_rel_post_cleanup(Relation onerel, VacuumParams *params, BufferAccessSt
 								 &relhasindex,
 								 &total_file_segs);
 
-	/* MERGE16_FIXME: How to set limits for ao */
-	vacuum_set_xid_limits(onerel,
-						  params->freeze_min_age,
-						  params->freeze_table_age,
-						  params->multixact_freeze_min_age,
-						  params->multixact_freeze_table_age,
-						  &OldestXmin, &FreezeLimit, &xidFullScanLimit,
-						  &MultiXactCutoff, &mxactFullScanLimit);
-
-	/* Causion: AO/AOCO use relallvisible to represent total segment file count */
+	/*
+	 * AO/AOCO tables have no per-tuple xmin/xmax, so freeze limits don't
+	 * apply. Pass InvalidTransactionId/InvalidMultiXactId to keep
+	 * relfrozenxid and relminmxid unchanged.
+	 */
 	vac_update_relstats(onerel,
 						relpages,
 						reltuples,
@@ -305,8 +295,8 @@ ao_vacuum_rel_post_cleanup(Relation onerel, VacuumParams *params, BufferAccessSt
 							  Heap's 'all visible pages', use this field to represent
 							  AO/AOCO's total segment file count */
 						relhasindex,
-						FreezeLimit,
-						MultiXactCutoff,
+						InvalidTransactionId,
+						InvalidMultiXactId,
 						NULL,
 						NULL,
 						false,
diff --git a/src/backend/executor/nodePartitionSelector.c b/src/backend/executor/nodePartitionSelector.c
index 7999a1a4d71..1a1e3affa85 100644
--- a/src/backend/executor/nodePartitionSelector.c
+++ b/src/backend/executor/nodePartitionSelector.c
@@ -101,7 +101,6 @@ ExecInitPartitionSelector(PartitionSelector *node, EState *estate, int eflags)
 	outerPlanState(psstate) = ExecInitNode(outerPlan(node), estate, eflags);
 
 	/* Create the working data structure for pruning. */
-	/* MERGE16_FIXME: This use of ExecInitPartitionPruning may be incorrect */
 	psstate->prune_state = CreatePartitionPruneState(&psstate->ps, node->part_prune_info);
 
 	return psstate;
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 76ce1e8fbea..6bb0f9a92a5 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -74,6 +74,7 @@ bool		gp_enable_sort_limit = false;
 #define UNSAFE_NOTIN_DISTINCTON_CLAUSE	(1 << 2)
 #define UNSAFE_NOTIN_PARTITIONBY_CLAUSE	(1 << 3)
 #define UNSAFE_TYPE_MISMATCH			(1 << 4)
+#define UNSAFE_HAS_SUBPLAN				(1 << 5)
 
 /* results of subquery_is_pushdown_safe */
 typedef struct pushdown_safety_info
@@ -4714,11 +4715,10 @@ check_output_expressions(Query *subquery, pushdown_safety_info *safetyInfo)
 			continue;
 		}
 
-		/* Refuse subplans */
+		/* Refuse subplans (Cloudberry-specific, see UNSAFE_HAS_SUBPLAN) */
 		if (contain_subplans((Node *) tle->expr))
 		{
-			/*.MERGE16_FIXME: should we add a new unsafe type? */
-			safetyInfo->unsafeFlags[tle->resno] |= UNSAFE_NOTIN_PARTITIONBY_CLAUSE;
+			safetyInfo->unsafeFlags[tle->resno] |= UNSAFE_HAS_SUBPLAN;
 			continue;
 		}
 	}
@@ -4896,7 +4896,8 @@ qual_is_pushdown_safe(Query *subquery, Index rti, RestrictInfo *rinfo,
 		{
 			if (safetyInfo->unsafeFlags[var->varattno] &
 				(UNSAFE_HAS_VOLATILE_FUNC | UNSAFE_HAS_SET_FUNC |
-				 UNSAFE_NOTIN_DISTINCTON_CLAUSE | UNSAFE_TYPE_MISMATCH))
+				 UNSAFE_NOTIN_DISTINCTON_CLAUSE | UNSAFE_TYPE_MISMATCH |
+				 UNSAFE_HAS_SUBPLAN))
 			{
 				safe = PUSHDOWN_UNSAFE;
 				break;
diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index ebbecff523f..407bb90cec2 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -1576,10 +1576,14 @@ FileAccess(File file)
 static void
 ReportTemporaryFileUsage(const char *path, off_t size)
 {
-	/* MERGE16_FIXME: Now the pgstat has not worked, so disable the report first */
-	return;
-	
-	pgstat_report_tempfile(size);
+	/*
+	 * pgstat_report_tempfile() accesses shared memory via dshash, which
+	 * may already be detached during process exit cleanup.  Calling it
+	 * from PathNameDeleteTemporaryDir's walkdir causes SIGSEGV in
+	 * dshash_find().  Guard with IsUnderPostmaster and proc_exit_inprogress.
+	 */
+	if (!proc_exit_inprogress)
+		pgstat_report_tempfile(size);
 
 	if (log_temp_files >= 0)
 	{
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0a390048819..8eba8a6d227 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1300,28 +1300,6 @@ exec_mpp_query(const char *query_string,
 		elog(ERROR, "MPPEXEC: received non-DML Plan");
 	commandType = plan->commandType;
 
-	// MERGE16_FIXME: Check if wo should remove requiredPerms in Query
-//	if ( slice )
-//	{
-//		/* Non root slices don't need update privileges. */
-//		if (sliceTable->localSlice != slice->rootIndex)
-//		{
-//			ListCell       *rtcell;
-//			RangeTblEntry  *rte;
-//			RTEPermissionInfo  *rte_permission;
-//			AclMode         removeperms = ACL_INSERT | ACL_UPDATE | ACL_DELETE | ACL_SELECT_FOR_UPDATE;
-//
-//			/* Just reading, so don't check INS/DEL/UPD permissions. */
-//			foreach(rtcell, plan->rtable)
-//			{
-//				rte = (RangeTblEntry *)lfirst(rtcell);
-//				if (rte->rtekind == RTE_RELATION &&
-//					0 != (rte->requiredPerms & removeperms))
-//					rte->requiredPerms &= ~removeperms;
-//			}
-//		}
-//	}
-
 	if (log_statement != LOGSTMT_NONE)
 	{
 	    /*
diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c
index a43dcb75398..beaeb669266 100644
--- a/src/backend/utils/activity/pgstat.c
+++ b/src/backend/utils/activity/pgstat.c
@@ -1301,8 +1301,7 @@ pgstat_get_kind_info(PgStat_Kind kind)
 void
 pgstat_assert_is_up(void)
 {
-	/* MERGE16_FIXME: Now the pgstat has not worked, so disable the assert first */
-//	Assert(pgstat_is_initialized && !pgstat_is_shutdown);
+	Assert(pgstat_is_initialized && !pgstat_is_shutdown);
 }
 #endif
 
diff --git a/src/backend/utils/adt/rowtypes.c b/src/backend/utils/adt/rowtypes.c
index 3250d285e02..f0fa5838e66 100644
--- a/src/backend/utils/adt/rowtypes.c
+++ b/src/backend/utils/adt/rowtypes.c
@@ -154,7 +154,6 @@ record_in(PG_FUNCTION_ARGS)
 		ptr++;
 	if (*ptr++ != '(')
 	{
-		ReleaseTupleDesc(tupdesc);
 		errsave(escontext,
 				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 				 errmsg("malformed record literal: \"%s\"", string),
@@ -186,7 +185,6 @@ record_in(PG_FUNCTION_ARGS)
 				ptr++;
 			else
 			{
-				ReleaseTupleDesc(tupdesc);
 				/* *ptr must be ')' */
 				errsave(escontext,
 						(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
@@ -214,7 +212,6 @@ record_in(PG_FUNCTION_ARGS)
 
 				if (ch == '\0')
 				{
-					ReleaseTupleDesc(tupdesc);
 					errsave(escontext,
 							(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 							 errmsg("malformed record literal: \"%s\"",
@@ -226,7 +223,6 @@ record_in(PG_FUNCTION_ARGS)
 				{
 					if (*ptr == '\0')
 					{
-						ReleaseTupleDesc(tupdesc);
 						errsave(escontext,
 								(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 								 errmsg("malformed record literal: \"%s\"",
@@ -285,7 +281,6 @@ record_in(PG_FUNCTION_ARGS)
 
 	if (*ptr++ != ')')
 	{
-		ReleaseTupleDesc(tupdesc);
 		errsave(escontext,
 				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 				 errmsg("malformed record literal: \"%s\"", string),
@@ -297,7 +292,6 @@ record_in(PG_FUNCTION_ARGS)
 		ptr++;
 	if (*ptr)
 	{
-		ReleaseTupleDesc(tupdesc);
 		errsave(escontext,
 				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 				 errmsg("malformed record literal: \"%s\"", string),
diff --git a/src/bin/pg_basebackup/bbstreamer_file.c b/src/bin/pg_basebackup/bbstreamer_file.c
index 504225f0959..6101cc2ab97 100644
--- a/src/bin/pg_basebackup/bbstreamer_file.c
+++ b/src/bin/pg_basebackup/bbstreamer_file.c
@@ -327,7 +327,6 @@ should_allow_existing_directory(const char *pathname)
 static void
 extract_directory(const char *filename, mode_t mode)
 {
-	/* MERGE16_FIXME: We should test forceoverwrite here ? */
 	if (pg_check_dir(filename) != 0)
 	{
 		/*
diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h
index d700f4a72cc..431cd7221a8 100644
--- a/src/include/commands/vacuum.h
+++ b/src/include/commands/vacuum.h
@@ -491,15 +491,6 @@ extern Size vac_max_items_to_alloc_size(int max_items);
 /* In postmaster/autovacuum.c */
 extern void AutoVacuumUpdateCostLimit(void);
 extern void VacuumUpdateCosts(void);
-extern void vacuum_set_xid_limits(Relation rel,
-								  int freeze_min_age, int freeze_table_age,
-								  int multixact_freeze_min_age,
-								  int multixact_freeze_table_age,
-								  TransactionId *oldestXmin,
-								  TransactionId *freezeLimit,
-								  TransactionId *xidFullScanLimit,
-								  MultiXactId *multiXactCutoff,
-								  MultiXactId *mxactFullScanLimit);
 /* in commands/vacuumparallel.c */
 extern ParallelVacuumState *parallel_vacuum_init(Relation rel, Relation *indrels,
 												 int nindexes, int nrequested_workers,
diff --git a/src/include/executor/execPartition.h b/src/include/executor/execPartition.h
index 22c4fc9a5e6..91bc97db8c6 100644
--- a/src/include/executor/execPartition.h
+++ b/src/include/executor/execPartition.h
@@ -130,14 +130,10 @@ extern ResultRelInfo *ExecFindPartition(ModifyTableState *mtstate,
 										EState *estate);
 extern void ExecCleanupTupleRouting(ModifyTableState *mtstate,
 									PartitionTupleRouting *proute);
-extern PartitionPruneState *ExecCreatePartitionPruneState(PlanState *planstate,
-														  PartitionPruneInfo *partitionpruneinfo);
 extern Bitmapset *ExecFindMatchingSubPlans(PartitionPruneState *prunestate,
 										   bool initial_prune,
 										   EState *estate,
 										   int nplans, List *join_prune_paramids);
-extern Bitmapset *ExecFindInitialMatchingSubPlans(PartitionPruneState *prunestate,
-												  int nsubplans);
 extern int get_partition_for_tuple(PartitionKey key, PartitionDesc partdesc,
 								   Datum *values, bool *isnull);
 
diff --git a/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out b/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out
index 2e7b32f1d74..44969ba7eea 100644
--- a/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out
+++ b/src/test/isolation2/expected/resgroup/resgroup_cpu_max_percent.out
@@ -33,8 +33,8 @@ CREATE
 -- verify_cpu_usage: calculate each QE's average cpu usage using all the data in
 -- the table cpu_usage_sample. And compare the average value to the expected value.
 -- return true if the practical value is close to the expected value.
-CREATE OR REPLACE FUNCTION verify_cpu_usage(groupname TEXT, expect_cpu_usage INT, err_rate INT) RETURNS BOOL AS $$ import json import functools 
-all_info = plpy.execute(''' SELECT sample::json->'{name}' AS cpu FROM cpu_usage_samples '''.format(name=groupname)) usage = float(all_info[0]['cpu']) 
+CREATE OR REPLACE FUNCTION verify_cpu_usage(groupname TEXT, expect_cpu_usage INT, err_rate INT) RETURNS BOOL AS $$ import json 
+all_info = plpy.execute(''' SELECT sample::json->'{name}' AS cpu FROM cpu_usage_samples '''.format(name=groupname)) usage = sum(float(row['cpu']) for row in all_info) / len(all_info) 
 return abs(usage - expect_cpu_usage) <= err_rate $$ LANGUAGE plpython3u;
 CREATE
 
diff --git a/src/test/isolation2/expected/vacuum_progress_column.out b/src/test/isolation2/expected/vacuum_progress_column.out
index fcc983f1e43..12a3bceb78f 100644
--- a/src/test/isolation2/expected/vacuum_progress_column.out
+++ b/src/test/isolation2/expected/vacuum_progress_column.out
@@ -339,15 +339,6 @@ select relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, he
 --------------------------
  Success:                 
 (1 row)
--- Trigger FTS probe repeatedly until mirror is marked as down, so that
--- FTS version change propagates to QD and gang gets reset.
-CREATE OR REPLACE FUNCTION wait_for_mirror_down(content_id int) RETURNS bool AS $$ declare /* in func */ retries int; /* in func */ begin /* in func */ retries := 60; /* in func */ loop /* in func */ perform gp_request_fts_probe_scan(); /* in func */ if (select status = 'd' from gp_segment_configuration where content = content_id and role = 'm') then /* in func */ return true; /* in func */ end if; /* in func */ if retries <= 0 then /* in func */ return false; /* in func */ end if; /* in func */ perform pg_sleep(1); /* in func */ retries := retries - 1; /* in func */ end loop; /* in func */ end; /* in func */ $$ language plpgsql;
-CREATE
-2: SELECT wait_for_mirror_down(1);
- wait_for_mirror_down 
-----------------------
- t                    
-(1 row)
 -- Ensure we enter into the target logic which stops cumulative data but
 -- initializes a new vacrelstats at the beginning of post-cleanup phase.
 -- Also all segments should reach to the same "vacuum_worker_changed" point
@@ -398,14 +389,14 @@ CREATE
 select gp_segment_id, relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, heap_blks_vacuumed, index_vacuum_count, max_dead_tuples, num_dead_tuples from gp_stat_progress_vacuum where gp_segment_id > -1;
  gp_segment_id | relname                   | phase                         | heap_blks_total | heap_blks_scanned | heap_blks_vacuumed | index_vacuum_count | max_dead_tuples | num_dead_tuples 
 ---------------+---------------------------+-------------------------------+-----------------+-------------------+--------------------+--------------------+-----------------+-----------------
- 2             | vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 9                  | 2                  | 0               | 0               
- 0             | vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 9                  | 2                  | 0               | 0               
- 1             | vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 9                  | 2                  | 0               | 0               
+ 2             | vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 0                  | 0                  | 0               | 0               
+ 0             | vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 0                  | 0                  | 0               | 0               
+ 1             | vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 0                  | 0                  | 0               | 0               
 (3 rows)
 select relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, heap_blks_vacuumed, index_vacuum_count, max_dead_tuples, num_dead_tuples from gp_stat_progress_vacuum_summary;
  relname                   | phase                         | heap_blks_total | heap_blks_scanned | heap_blks_vacuumed | index_vacuum_count | max_dead_tuples | num_dead_tuples 
 ---------------------------+-------------------------------+-----------------+-------------------+--------------------+--------------------+-----------------+-----------------
- vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 27                 | 6                  | 0               | 0               
+ vacuum_progress_ao_column | append-optimized post-cleanup | 0               | 0                 | 0                  | 0                  | 0               | 0               
 (1 row)
 
 2: SELECT gp_inject_fault('vacuum_ao_post_cleanup_end', 'reset', dbid) FROM gp_segment_configuration WHERE content > -1 AND role = 'p';
diff --git a/src/test/isolation2/expected/vacuum_progress_row.out b/src/test/isolation2/expected/vacuum_progress_row.out
index 29809709eab..ef39d8edaf3 100644
--- a/src/test/isolation2/expected/vacuum_progress_row.out
+++ b/src/test/isolation2/expected/vacuum_progress_row.out
@@ -293,8 +293,6 @@ SELECT n_live_tup, n_dead_tup, last_vacuum is not null as has_last_vacuum, vacuu
 -- phase (at injecting point vacuum_ao_post_cleanup_end), which is different from above case
 -- in which vacuum worker isn't changed.
 
-CREATE OR REPLACE FUNCTION wait_for_mirror_down(content_id int) RETURNS bool AS $$ declare /* in func */ retries int; /* in func */ begin /* in func */ retries := 60; /* in func */ loop /* in func */ perform gp_request_fts_probe_scan(); /* in func */ if (select status = 'd' from gp_segment_configuration where content = content_id and role = 'm') then /* in func */ return true; /* in func */ end if; /* in func */ if retries <= 0 then /* in func */ return false; /* in func */ end if; /* in func */ perform pg_sleep(1); /* in func */ retries := retries - 1; /* in func */ end loop; /* in func */ end; /* in func */ $$ language plpgsql;
-CREATE
 DROP TABLE IF EXISTS vacuum_progress_ao_row;
 DROP
 CREATE TABLE vacuum_progress_ao_row(i int, j int);
@@ -395,13 +393,6 @@ select relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, he
 --------------------------
  Success:                 
 (1 row)
--- Trigger FTS probe repeatedly until mirror is marked as down, so that
--- FTS version change propagates to QD and gang gets reset.
-2: SELECT wait_for_mirror_down(1);
- wait_for_mirror_down 
-----------------------
- t                    
-(1 row)
 -- Ensure we enter into the target logic which stops cumulative data but
 -- initializes a new vacrelstats at the beginning of post-cleanup phase.
 -- Also all segments should reach to the same "vacuum_worker_changed" point
@@ -606,13 +597,6 @@ select relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, he
 --------------------------
  Success:                 
 (1 row)
--- Trigger FTS probe repeatedly until mirror is marked as down, so that
--- FTS version change propagates to QD and gang gets reset.
-2: SELECT wait_for_mirror_down(1);
- wait_for_mirror_down 
-----------------------
- t                    
-(1 row)
 -- Ensure we enter into the target logic which stops cumulative data but
 -- initializes a new vacrelstats at the beginning of post-cleanup phase.
 -- Also all segments should reach to the same "vacuum_worker_changed" point
diff --git a/src/test/isolation2/isolation2_schedule b/src/test/isolation2/isolation2_schedule
index 7e7e4220d12..82d23731fb6 100644
--- a/src/test/isolation2/isolation2_schedule
+++ b/src/test/isolation2/isolation2_schedule
@@ -253,8 +253,7 @@ test: segwalrep/dtm_recovery_on_standby
 test: segwalrep/commit_blocking_on_standby
 test: segwalrep/dtx_recovery_wait_lsn
 
-# MERGE16_FIXME: enable this case latter
-# test: segwalrep/select_throttle
+test: segwalrep/select_throttle
 test: segwalrep/startup_rename_prepared_xlog
 test: fts_manual_probe
 test: fts_session_reset
diff --git a/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql b/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql
index c7dfc9f60b0..89fa523cc88 100644
--- a/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql
+++ b/src/test/isolation2/sql/resgroup/resgroup_cpu_max_percent.sql
@@ -38,12 +38,11 @@ $$ LANGUAGE plpython3u;
 CREATE OR REPLACE FUNCTION verify_cpu_usage(groupname TEXT, expect_cpu_usage INT, err_rate INT)
 RETURNS BOOL AS $$
     import json
-    import functools
 
     all_info = plpy.execute('''
         SELECT sample::json->'{name}' AS cpu FROM cpu_usage_samples
     '''.format(name=groupname))
-    usage = float(all_info[0]['cpu'])
+    usage = sum(float(row['cpu']) for row in all_info) / len(all_info)
 
     return abs(usage - expect_cpu_usage) <= err_rate
 $$ LANGUAGE plpython3u;
diff --git a/src/test/isolation2/sql/vacuum_progress_column.sql b/src/test/isolation2/sql/vacuum_progress_column.sql
index 519c3e37200..60250368b46 100644
--- a/src/test/isolation2/sql/vacuum_progress_column.sql
+++ b/src/test/isolation2/sql/vacuum_progress_column.sql
@@ -141,27 +141,6 @@ select relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, he
 2: SELECT gp_inject_fault('vacuum_worker_changed', 'suspend', dbid) FROM gp_segment_configuration WHERE content > -1 AND role = 'p';
 -- resume walsender and let it exit so that mirror stop can be detected
 2: SELECT gp_inject_fault_infinite('wal_sender_loop', 'reset', dbid) FROM gp_segment_configuration WHERE role = 'p' and content = 1;
--- Trigger FTS probe repeatedly until mirror is marked as down, so that
--- FTS version change propagates to QD and gang gets reset.
-CREATE OR REPLACE FUNCTION wait_for_mirror_down(content_id int) RETURNS bool AS $$
-declare /* in func */
-  retries int; /* in func */
-begin /* in func */
-  retries := 60; /* in func */
-  loop /* in func */
-    perform gp_request_fts_probe_scan(); /* in func */
-    if (select status = 'd' from gp_segment_configuration where content = content_id and role = 'm') then /* in func */
-      return true; /* in func */
-    end if; /* in func */
-    if retries <= 0 then /* in func */
-      return false; /* in func */
-    end if; /* in func */
-    perform pg_sleep(1); /* in func */
-    retries := retries - 1; /* in func */
-  end loop; /* in func */
-end; /* in func */
-$$ language plpgsql;
-2: SELECT wait_for_mirror_down(1);
 -- Ensure we enter into the target logic which stops cumulative data but
 -- initializes a new vacrelstats at the beginning of post-cleanup phase.
 -- Also all segments should reach to the same "vacuum_worker_changed" point
diff --git a/src/test/isolation2/sql/vacuum_progress_row.sql b/src/test/isolation2/sql/vacuum_progress_row.sql
index 125368df72b..c832a1fd0df 100644
--- a/src/test/isolation2/sql/vacuum_progress_row.sql
+++ b/src/test/isolation2/sql/vacuum_progress_row.sql
@@ -107,24 +107,6 @@ SELECT n_live_tup, n_dead_tup, last_vacuum is not null as has_last_vacuum, vacuu
 -- phase (at injecting point vacuum_ao_post_cleanup_end), which is different from above case
 -- in which vacuum worker isn't changed.
 
-CREATE OR REPLACE FUNCTION wait_for_mirror_down(content_id int) RETURNS bool AS $$
-declare /* in func */
-  retries int; /* in func */
-begin /* in func */
-  retries := 60; /* in func */
-  loop /* in func */
-    perform gp_request_fts_probe_scan(); /* in func */
-    if (select status = 'd' from gp_segment_configuration where content = content_id and role = 'm') then /* in func */
-      return true; /* in func */
-    end if; /* in func */
-    if retries <= 0 then /* in func */
-      return false; /* in func */
-    end if; /* in func */
-    perform pg_sleep(1); /* in func */
-    retries := retries - 1; /* in func */
-  end loop; /* in func */
-end; /* in func */
-$$ language plpgsql;
 DROP TABLE IF EXISTS vacuum_progress_ao_row;
 CREATE TABLE vacuum_progress_ao_row(i int, j int);
 CREATE INDEX on vacuum_progress_ao_row(i);
@@ -164,9 +146,6 @@ select relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, he
 2: SELECT gp_inject_fault('vacuum_worker_changed', 'suspend', dbid) FROM gp_segment_configuration WHERE content > -1 AND role = 'p';
 -- resume walsender and let it exit so that mirror stop can be detected
 2: SELECT gp_inject_fault_infinite('wal_sender_loop', 'reset', dbid) FROM gp_segment_configuration WHERE role = 'p' and content = 1;
--- Trigger FTS probe repeatedly until mirror is marked as down, so that
--- FTS version change propagates to QD and gang gets reset.
-2: SELECT wait_for_mirror_down(1);
 -- Ensure we enter into the target logic which stops cumulative data but
 -- initializes a new vacrelstats at the beginning of post-cleanup phase.
 -- Also all segments should reach to the same "vacuum_worker_changed" point
@@ -241,9 +220,6 @@ select relid::regclass as relname, phase, heap_blks_total, heap_blks_scanned, he
 2: SELECT gp_inject_fault('vacuum_worker_changed', 'suspend', dbid) FROM gp_segment_configuration WHERE content > -1 AND role = 'p';
 -- resume walsender and let it exit so that mirror stop can be detected
 2: SELECT gp_inject_fault_infinite('wal_sender_loop', 'reset', dbid) FROM gp_segment_configuration WHERE role = 'p' and content = 1;
--- Trigger FTS probe repeatedly until mirror is marked as down, so that
--- FTS version change propagates to QD and gang gets reset.
-2: SELECT wait_for_mirror_down(1);
 -- Ensure we enter into the target logic which stops cumulative data but
 -- initializes a new vacrelstats at the beginning of post-cleanup phase.
 -- Also all segments should reach to the same "vacuum_worker_changed" point
diff --git a/src/test/regress/expected/rowtypes.out b/src/test/regress/expected/rowtypes.out
index ecd4ee0deb3..d86bab812db 100644
--- a/src/test/regress/expected/rowtypes.out
+++ b/src/test/regress/expected/rowtypes.out
@@ -70,41 +70,36 @@ LINE 1: select '(Joe,Blow) /'::fullname;
                ^
 DETAIL:  Junk after right parenthesis.
 -- test non-error-throwing API
--- MERGE16_FIXME: 
--- The greenplum implement complex type by itself, postgres implement
--- it now. should we use the complex type implemented by postgres.
--- start_ignore
-SELECT pg_input_is_valid('(1,2)', 'complex');
+SELECT pg_input_is_valid('(1,2)', 'complex_t');
  pg_input_is_valid 
 -------------------
  t
 (1 row)
 
-SELECT pg_input_is_valid('(1,2', 'complex');
+SELECT pg_input_is_valid('(1,2', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT pg_input_is_valid('(1,zed)', 'complex');
+SELECT pg_input_is_valid('(1,zed)', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,zed)', 'complex');
+SELECT * FROM pg_input_error_info('(1,zed)', 'complex_t');
                         message                        | detail | hint | sql_error_code 
 -------------------------------------------------------+--------+------+----------------
  invalid input syntax for type double precision: "zed" |        |      | 22P02
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,1e400)', 'complex');
+SELECT * FROM pg_input_error_info('(1,1e400)', 'complex_t');
                       message                      | detail | hint | sql_error_code 
 ---------------------------------------------------+--------+------+----------------
  "1e400" is out of range for type double precision |        |      | 22003
 (1 row)
 
--- end_ignore
 create temp table quadtable(f1 int, q quad);
 insert into quadtable values (1, ((3.3,4.4),(5.5,6.6)));
 insert into quadtable values (2, ((null,4.4),(5.5,6.6)));
diff --git a/src/test/regress/expected/rowtypes_optimizer.out b/src/test/regress/expected/rowtypes_optimizer.out
index e937a160d96..6edc5cbda2a 100644
--- a/src/test/regress/expected/rowtypes_optimizer.out
+++ b/src/test/regress/expected/rowtypes_optimizer.out
@@ -70,41 +70,36 @@ LINE 1: select '(Joe,Blow) /'::fullname;
                ^
 DETAIL:  Junk after right parenthesis.
 -- test non-error-throwing API
--- MERGE16_FIXME: 
--- The greenplum implement complex type by itself, postgres implement
--- it now. should we use the complex type implemented by postgres.
--- start_ignore
-SELECT pg_input_is_valid('(1,2)', 'complex');
+SELECT pg_input_is_valid('(1,2)', 'complex_t');
  pg_input_is_valid 
 -------------------
  t
 (1 row)
 
-SELECT pg_input_is_valid('(1,2', 'complex');
+SELECT pg_input_is_valid('(1,2', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT pg_input_is_valid('(1,zed)', 'complex');
+SELECT pg_input_is_valid('(1,zed)', 'complex_t');
  pg_input_is_valid 
 -------------------
  f
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,zed)', 'complex');
+SELECT * FROM pg_input_error_info('(1,zed)', 'complex_t');
                         message                        | detail | hint | sql_error_code 
 -------------------------------------------------------+--------+------+----------------
  invalid input syntax for type double precision: "zed" |        |      | 22P02
 (1 row)
 
-SELECT * FROM pg_input_error_info('(1,1e400)', 'complex');
+SELECT * FROM pg_input_error_info('(1,1e400)', 'complex_t');
                       message                      | detail | hint | sql_error_code 
 ---------------------------------------------------+--------+------+----------------
  "1e400" is out of range for type double precision |        |      | 22003
 (1 row)
 
--- end_ignore
 create temp table quadtable(f1 int, q quad);
 insert into quadtable values (1, ((3.3,4.4),(5.5,6.6)));
 insert into quadtable values (2, ((null,4.4),(5.5,6.6)));
diff --git a/src/test/regress/sql/rowtypes.sql b/src/test/regress/sql/rowtypes.sql
index 8175022c3f4..655fe4c0349 100644
--- a/src/test/regress/sql/rowtypes.sql
+++ b/src/test/regress/sql/rowtypes.sql
@@ -42,16 +42,11 @@ select ' (Joe,Blow)  '::fullname;  -- ok, extra whitespace
 select '(Joe,Blow) /'::fullname;  -- bad
 
 -- test non-error-throwing API
--- MERGE16_FIXME: 
--- The greenplum implement complex type by itself, postgres implement
--- it now. should we use the complex type implemented by postgres.
--- start_ignore
-SELECT pg_input_is_valid('(1,2)', 'complex');
-SELECT pg_input_is_valid('(1,2', 'complex');
-SELECT pg_input_is_valid('(1,zed)', 'complex');
-SELECT * FROM pg_input_error_info('(1,zed)', 'complex');
-SELECT * FROM pg_input_error_info('(1,1e400)', 'complex');
--- end_ignore
+SELECT pg_input_is_valid('(1,2)', 'complex_t');
+SELECT pg_input_is_valid('(1,2', 'complex_t');
+SELECT pg_input_is_valid('(1,zed)', 'complex_t');
+SELECT * FROM pg_input_error_info('(1,zed)', 'complex_t');
+SELECT * FROM pg_input_error_info('(1,1e400)', 'complex_t');
 
 create temp table quadtable(f1 int, q quad);
 
diff --git a/src/test/singlenode_isolation2/expected/prevent_ao_wal.out b/src/test/singlenode_isolation2/expected/prevent_ao_wal.out
index fb5f556ce91..be069bcee39 100644
--- a/src/test/singlenode_isolation2/expected/prevent_ao_wal.out
+++ b/src/test/singlenode_isolation2/expected/prevent_ao_wal.out
@@ -15,7 +15,7 @@
 
 GP_IGNORE: formatted by atmsort.pm
 -- start_matchignore
--- m/pg_waldump: fatal: error in WAL record at */
+-- m/pg_waldump: (fatal|error): .*/
 -- m/.*The 'DISTRIBUTED BY' clause determines the distribution of data*/
 -- m/.*Table doesn't have 'DISTRIBUTED BY' clause*/
 -- end_matchignore
@@ -64,31 +64,28 @@ VACUUM
 -1Uq: ... <quitting>
 
 -- Validate wal records
--- MERGE16_FIXME: this should throw a 'pg_waldump: error: error in WAL record at 0/40247EF8: invalid record length at 0/40247F28: expected at least 24, got 0' ERROR, fix it later
--- start_ignore
 ! last_wal_file=$(psql -At -c "SELECT pg_walfile_name(pg_current_wal_lsn())" postgres) && pg_waldump ${last_wal_file} -p ${COORDINATOR_DATA_DIRECTORY}/pg_wal -r appendonly;
-rmgr: Appendonly  len (rec/tot):    186/   186, tx:      12661, lsn: 0/F8000178, prev 0/F8000128, desc: APPENDONLY_INSERT insert: rel 1663/221728/180472 seg/offset:0/0 len:136
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:      12662, lsn: 0/F8000400, prev 0/F80003C0, desc: APPENDONLY_INSERT insert: rel 1663/221728/180476 seg/offset:128/0 len:0
-rmgr: Appendonly  len (rec/tot):    130/   130, tx:      12662, lsn: 0/F8000490, prev 0/F8000440, desc: APPENDONLY_INSERT insert: rel 1663/221728/180476 seg/offset:0/0 len:80
-rmgr: Appendonly  len (rec/tot):    130/   130, tx:      12662, lsn: 0/F8000520, prev 0/F8000490, desc: APPENDONLY_INSERT insert: rel 1663/221728/180476 seg/offset:128/0 len:80
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:          0, lsn: 0/F8000840, prev 0/F8000810, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180472 seg/offset:0/136
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:      12664, lsn: 0/F8000A18, prev 0/F80009D8, desc: APPENDONLY_INSERT insert: rel 1663/221728/180472 seg/offset:1/0 len:0
-rmgr: Appendonly  len (rec/tot):    138/   138, tx:      12664, lsn: 0/F8000B38, prev 0/F8000AF8, desc: APPENDONLY_INSERT insert: rel 1663/221728/180472 seg/offset:1/0 len:88
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:      12665, lsn: 0/F8000C98, prev 0/F8000C68, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180472 seg/offset:0/0
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:          0, lsn: 0/F80412F8, prev 0/F80412C8, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180476 seg/offset:0/80
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:          0, lsn: 0/F8041338, prev 0/F80412F8, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180476 seg/offset:128/80
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:          0, lsn: 0/F8307118, prev 0/F83070E8, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180472 seg/offset:1/88
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:          0, lsn: 0/F8307150, prev 0/F8307118, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180472 seg/offset:0/0
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:          0, lsn: 0/F8307208, prev 0/F83071D8, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180476 seg/offset:0/80
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:          0, lsn: 0/F8307248, prev 0/F8307208, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180476 seg/offset:128/80
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:      12673, lsn: 0/F8307440, prev 0/F8307400, desc: APPENDONLY_INSERT insert: rel 1663/221728/180476 seg/offset:1/0 len:0
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:      12673, lsn: 0/F8307480, prev 0/F8307440, desc: APPENDONLY_INSERT insert: rel 1663/221728/180476 seg/offset:129/0 len:0
-rmgr: Appendonly  len (rec/tot):    114/   114, tx:      12673, lsn: 0/F83075A0, prev 0/F8307560, desc: APPENDONLY_INSERT insert: rel 1663/221728/180476 seg/offset:1/0 len:64
-rmgr: Appendonly  len (rec/tot):    114/   114, tx:      12673, lsn: 0/F8307620, prev 0/F83075A0, desc: APPENDONLY_INSERT insert: rel 1663/221728/180476 seg/offset:129/0 len:64
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:      12674, lsn: 0/F8307780, prev 0/F8307750, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180476 seg/offset:0/0
-rmgr: Appendonly  len (rec/tot):     50/    50, tx:      12674, lsn: 0/F83077C0, prev 0/F8307780, desc: APPENDONLY_TRUNCATE truncate: rel 1663/221728/180476 seg/offset:128/0
+rmgr: Appendonly  len (rec/tot):    186/   186, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:0/0 len:136
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:128/0 len:0
+rmgr: Appendonly  len (rec/tot):    130/   130, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:0/0 len:80
+rmgr: Appendonly  len (rec/tot):    130/   130, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:128/0 len:80
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:0/136
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:1/0 len:0
+rmgr: Appendonly  len (rec/tot):    138/   138, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:1/0 len:88
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:0/0
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:0/80
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:128/80
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:1/88
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:0/0
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:0/80
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:128/80
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:1/0 len:0
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:129/0 len:0
+rmgr: Appendonly  len (rec/tot):    114/   114, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:1/0 len:64
+rmgr: Appendonly  len (rec/tot):    114/   114, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_INSERT insert: rel ####/######/###### seg/offset:129/0 len:64
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:0/0
+rmgr: Appendonly  len (rec/tot):     50/    50, tx: ##, lsn: #/########, prev #/########, desc: APPENDONLY_TRUNCATE truncate: rel ####/######/###### seg/offset:128/0
 
--- end_ignore
 
 -- *********** Set wal_level=minimal **************
 !\retcode gpconfig -c wal_level -v minimal --masteronly;
@@ -124,10 +121,8 @@ DELETE 5
 VACUUM
 
 -- Validate wal records
--- start_ignore
 ! last_wal_file=$(psql -At -c "SELECT pg_walfile_name(pg_current_wal_lsn())" postgres) && pg_waldump ${last_wal_file} -p ${COORDINATOR_DATA_DIRECTORY}/pg_wal -r appendonly;
 
--- end_ignore
 
 -1U: DROP TABLE ao_foo;
 DROP
diff --git a/src/test/singlenode_isolation2/input/workfile_mgr_test.source b/src/test/singlenode_isolation2/input/workfile_mgr_test.source
index 30f03315d7e..f5e189e694b 100644
--- a/src/test/singlenode_isolation2/input/workfile_mgr_test.source
+++ b/src/test/singlenode_isolation2/input/workfile_mgr_test.source
@@ -57,7 +57,7 @@ language plpgsql volatile execute on all segments;
 
 -- start_ignore
 !\retcode gpconfig -c gp_workfile_max_entries -v 32 --skipvalidation;
-!\retcode gpstop -ari;
+!\retcode gpstop -arf;
 -- end_ignore
 
 -- setup for workfile made in temp tablespace test
@@ -80,7 +80,7 @@ language plpgsql volatile execute on all segments;
 
 -- start_ignore
 !\retcode gpconfig -r gp_workfile_max_entries --skipvalidation;
-!\retcode gpstop -ari;
+!\retcode gpstop -arf;
 -- end_ignore
 
 -- test workset cleanup
diff --git a/src/test/singlenode_isolation2/isolation2_schedule b/src/test/singlenode_isolation2/isolation2_schedule
index adf4e6c0ede..7e5266d1c84 100644
--- a/src/test/singlenode_isolation2/isolation2_schedule
+++ b/src/test/singlenode_isolation2/isolation2_schedule
@@ -211,8 +211,7 @@ test: uao/bitmapindex_rescan_column
 # test: add_column_after_vacuum_skip_drop_column
 # test: vacuum_after_vacuum_skip_drop_column
 # test workfile_mgr
-# MERGE16_FIXME: enable workfile_mgr_test later
-#test: workfile_mgr_test
+test: workfile_mgr_test
 # test: pg_basebackup
 # test: pg_basebackup_with_tablespaces
 test: enable_autovacuum
diff --git a/src/test/singlenode_isolation2/output/workfile_mgr_test.source b/src/test/singlenode_isolation2/output/workfile_mgr_test.source
index a6821ecc38b..5fcbd06dde4 100644
--- a/src/test/singlenode_isolation2/output/workfile_mgr_test.source
+++ b/src/test/singlenode_isolation2/output/workfile_mgr_test.source
@@ -30,7 +30,7 @@ CREATE
 
 -- end_ignore
 (exited with code 0)
-!\retcode gpstop -ari;
+!\retcode gpstop -arf;
 -- start_ignore
 20200923:12:05:57:014232 gpstop:mdw:gpadmin-[INFO]:-Starting gpstop with args: -ari
 20200923:12:05:57:014232 gpstop:mdw:gpadmin-[INFO]:-Gathering information and validating the environment...
@@ -122,7 +122,7 @@ DROP
 
 -- end_ignore
 (exited with code 0)
-!\retcode gpstop -ari;
+!\retcode gpstop -arf;
 -- start_ignore
 20230630:09:01:15:025313 gpstop:merge:gpadmin-[INFO]:-Starting gpstop with args: -ari
 20230630:09:01:15:025313 gpstop:merge:gpadmin-[INFO]:-Gathering information and validating the environment...
diff --git a/src/test/singlenode_isolation2/sql/prevent_ao_wal.sql b/src/test/singlenode_isolation2/sql/prevent_ao_wal.sql
index 06b64591658..c9a32051f18 100644
--- a/src/test/singlenode_isolation2/sql/prevent_ao_wal.sql
+++ b/src/test/singlenode_isolation2/sql/prevent_ao_wal.sql
@@ -14,7 +14,7 @@
 -- validate WAL records on the coordinator.
 
 -- start_matchignore
--- m/pg_waldump: fatal: error in WAL record at */
+-- m/pg_waldump: (fatal|error): .*/
 -- m/.*The 'DISTRIBUTED BY' clause determines the distribution of data*/
 -- m/.*Table doesn't have 'DISTRIBUTED BY' clause*/
 -- end_matchignore
@@ -49,10 +49,7 @@
 -1Uq:
 
 -- Validate wal records
--- MERGE16_FIXME: this should throw a 'pg_waldump: error: error in WAL record at 0/40247EF8: invalid record length at 0/40247F28: expected at least 24, got 0' ERROR, fix it later
--- start_ignore
 ! last_wal_file=$(psql -At -c "SELECT pg_walfile_name(pg_current_wal_lsn())" postgres) && pg_waldump ${last_wal_file} -p ${COORDINATOR_DATA_DIRECTORY}/pg_wal -r appendonly;
--- end_ignore
 
 -- *********** Set wal_level=minimal **************
 !\retcode gpconfig -c wal_level -v minimal --masteronly;
@@ -75,9 +72,7 @@
 -1U: VACUUM;
 
 -- Validate wal records
--- start_ignore
 ! last_wal_file=$(psql -At -c "SELECT pg_walfile_name(pg_current_wal_lsn())" postgres) && pg_waldump ${last_wal_file} -p ${COORDINATOR_DATA_DIRECTORY}/pg_wal -r appendonly;
--- end_ignore
 
 -1U: DROP TABLE ao_foo; 
 -1U: DROP TABLE aoco_foo;