tests: added tests.replica.ReplicaTest.test_start_stop_lsn_in_the_same_segno

Author: gsmolk

tests/replica.py

@@ -1073,6 +1073,87 @@ def test_replica_toast(self):
         # Clean after yourself
         self.del_test_dir(module_name, fname)
 
+    # @unittest.skip("skip")
+    def test_start_stop_lsn_in_the_same_segno(self):
+        """
+        """
+        fname = self.id().split('.')[3]
+        backup_dir = os.path.join(self.tmp_path, module_name, fname, 'backup')
+        master = self.make_simple_node(
+            base_dir=os.path.join(module_name, fname, 'master'),
+            set_replication=True,
+            initdb_params=['--data-checksums'],
+            pg_options={
+                'autovacuum': 'off',
+                'checkpoint_timeout': '1h',
+                'wal_level': 'replica',
+                'shared_buffers': '128MB'})
+
+        if self.get_version(master) < self.version_to_num('9.6.0'):
+            self.del_test_dir(module_name, fname)
+            return unittest.skip(
+                'Skipped because backup from replica is not supported in PG 9.5')
+
+        self.init_pb(backup_dir)
+        self.add_instance(backup_dir, 'master', master)
+        master.slow_start()
+
+        # freeze bgwriter to get rid of RUNNING XACTS records
+        bgwriter_pid = master.auxiliary_pids[ProcessType.BackgroundWriter][0]
+        gdb_checkpointer = self.gdb_attach(bgwriter_pid)
+
+        self.backup_node(backup_dir, 'master', master, options=['--stream'])
+
+        # Create replica
+        replica = self.make_simple_node(
+            base_dir=os.path.join(module_name, fname, 'replica'))
+        replica.cleanup()
+        self.restore_node(backup_dir, 'master', replica)
+
+        # Settings for Replica
+        self.add_instance(backup_dir, 'replica', replica)
+        self.set_replica(master, replica, synchronous=True)
+
+        replica.slow_start(replica=True)
+
+        self.switch_wal_segment(master)
+        self.switch_wal_segment(master)
+
+        master.safe_psql(
+            'postgres',
+            'CREATE TABLE t1 AS '
+            'SELECT i, repeat(md5(i::text),5006056) AS fat_attr '
+            'FROM generate_series(0,10) i')
+
+        master.safe_psql(
+            'postgres',
+            'CHECKPOINT')
+
+        self.wait_until_replica_catch_with_master(master, replica)
+
+        sleep(60)
+
+        self.backup_node(
+            backup_dir, 'replica', replica,
+            options=[
+                '--archive-timeout=30',
+                '--log-level-console=LOG',
+                '--no-validate',
+                '--stream'],
+            return_id=False)
+
+        self.backup_node(
+            backup_dir, 'replica', replica,
+            options=[
+                '--archive-timeout=30',
+                '--log-level-console=LOG',
+                '--no-validate',
+                '--stream'],
+            return_id=False)
+
+        # Clean after yourself
+        self.del_test_dir(module_name, fname)
+
     @unittest.skip("skip")
     def test_replica_promote_1(self):
         """