Add description of test_logical_replication_ondemand_download test

test_runner/regress/test_logical_replication.py

@@ -624,3 +624,52 @@ def test_subscriber_synchronous_commit(neon_simple_env: NeonEnv, vanilla_pg: Van
     log.info("waiting for sync after restart")
     logical_replication_wait_flush_lsn_sync(vanilla_pg)
     assert sub.safe_psql_scalar("SELECT count(*) FROM t") == 1000
+
+
+# Test that we can use max_slot_wal_keep_size to restrict WAL size on the local disk but
+# do not invalidate obsolete (unacked) slot relying on on-demand WAL download feature.
+def test_logical_replication_ondemand_download(neon_simple_env: NeonEnv, vanilla_pg):
+    env = neon_simple_env
+
+    env.create_branch("publisher")
+    endpoint = env.endpoints.create(
+        "publisher", config_lines=["max_slot_wal_keep_size=1MB", "max_wal_size=32MB"]
+    )
+    endpoint.start()
+
+    pg_conn = endpoint.connect()
+    cur = pg_conn.cursor()
+
+    cur.execute(
+        "create table t(x integer primary key, fillter text default repeat(' ', 1000)) with (fillfactor=10)"
+    )
+    cur.execute("create publication pub1 for table t")
+
+    # now start subscriber
+    vanilla_pg.configure(["wal_level=logical"])
+    vanilla_pg.start()
+    vanilla_pg.safe_psql(
+        "create table t(x integer primary key, fillter text default repeat(' ', 1000)) with (fillfactor=10)"
+    )
+
+    connstr = endpoint.connstr().replace("'", "''")
+    log.info(f"ep connstr is {endpoint.connstr()}, subscriber connstr {vanilla_pg.connstr()}")
+    vanilla_pg.safe_psql(f"create subscription sub1 connection '{connstr}' publication pub1")
+
+    # Stop subscriber...
+    vanilla_pg.stop()
+
+    # ... and insert 800Mb data which should be delivered to subscriber after restart
+    cur.execute("insert into t values (generate_series(1,100000))")
+
+    # Check that WAL is truncated
+    assert endpoint.get_pg_wal_size() < 800
+
+    # Start subscriber...
+    vanilla_pg.start()
+
+    # Check that subscribers receives all data
+    def check_that_changes_propagated():
+        assert vanilla_pg.safe_psql("select count(*) from t")[0][0] == 100000
+
+    wait_until(check_that_changes_propagated, timeout=200.0, interval=10.0)

vendor/revisions.json

@@ -1,18 +1,18 @@
 {
   "v17": [
     "17.5",
-    "db424d42d748f8ad91ac00e28db2c7f2efa42f7f"
+    "611710b6ed40269e7c09c8095c5e916c5fd19417"
   ],
   "v16": [
     "16.9",
-    "7a4c0eacaeb9b97416542fa19103061c166460b1"
+    "35f6d1ba51577b03ba2affc238ba190541434f6d"
   ],
   "v15": [
     "15.13",
-    "8c3249f36c7df6ac0efb8ee9f1baf4aa1b83e5c9"
+    "d1627bff1c5f8172845406a3b85b7aa84a7760e2"
   ],
   "v14": [
     "14.18",
-    "9085654ee8022d5cc4ca719380a1dc53e5e3246f"
+    "ced5045624096851658c6de00c5b8930cfea8755"
   ]
 }