Add tests for concurrent INSERT and VACUUM behaviour

src/test/regress/expected/isolation_insert_vs_vacuum.out

@@ -0,0 +1,36 @@
+Parsed test spec with 2 sessions
+
+starting permutation: s1-begin s1-insert s2-vacuum-analyze s1-commit
+create_distributed_table
+
+               
+step s1-begin: 
+    BEGIN;
+
+step s1-insert: 
+    INSERT INTO test_insert_vacuum VALUES(1, 1);
+
+step s2-vacuum-analyze: 
+    VACUUM ANALYZE test_insert_vacuum;
+
+step s1-commit: 
+    COMMIT;
+
+
+starting permutation: s1-begin s1-insert s2-vacuum-full s1-commit
+create_distributed_table
+
+               
+step s1-begin: 
+    BEGIN;
+
+step s1-insert: 
+    INSERT INTO test_insert_vacuum VALUES(1, 1);
+
+step s2-vacuum-full: 
+    VACUUM FULL test_insert_vacuum;
+ <waiting ...>
+step s1-commit: 
+    COMMIT;
+
+step s2-vacuum-full: <... completed>

src/test/regress/isolation_schedule

@@ -7,4 +7,6 @@ test: isolation_cluster_management
 
 test: isolation_dml_vs_repair isolation_copy_placement_vs_copy_placement
 test: isolation_concurrent_dml isolation_data_migration
-test: isolation_drop_shards isolation_copy_placement_vs_modification 
+test: isolation_drop_shards isolation_copy_placement_vs_modification
+
+test: isolation_insert_vs_vacuum

src/test/regress/specs/isolation_insert_vs_vacuum.spec

@@ -0,0 +1,47 @@
+setup
+{
+    SET citus.shard_replication_factor TO 1;
+    CREATE TABLE test_insert_vacuum(column1 int, column2 int);
+    SELECT create_distributed_table('test_insert_vacuum', 'column1');
+}
+
+teardown
+{
+    DROP TABLE test_insert_vacuum;
+}
+
+session "s1"
+
+step "s1-begin"
+{
+    BEGIN;
+}
+
+step "s1-insert"
+{
+    INSERT INTO test_insert_vacuum VALUES(1, 1);
+}
+
+step "s1-commit"
+{
+    COMMIT;
+}
+
+session "s2"
+
+step "s2-vacuum-analyze"
+{
+    VACUUM ANALYZE test_insert_vacuum;
+}
+
+step "s2-vacuum-full"
+{
+    VACUUM FULL test_insert_vacuum;
+}
+
+# INSERT and VACUUM ANALYZE should not block each other.
+permutation "s1-begin" "s1-insert" "s2-vacuum-analyze" "s1-commit"
+
+# INSERT and VACUUM FULL should block each other.
+permutation "s1-begin" "s1-insert" "s2-vacuum-full" "s1-commit"
+