-- -- MUTLI_SHARD_REBALANCER -- CREATE TABLE dist_table_test(a int primary key); SELECT create_distributed_table('dist_table_test', 'a'); create_distributed_table --------------------------------------------------------------------- (1 row) CREATE TABLE ref_table_test(a int primary key); SELECT create_reference_table('ref_table_test'); create_reference_table --------------------------------------------------------------------- (1 row) -- make sure that all rebalance operations works fine when -- reference tables are replicated to the coordinator SELECT 1 FROM master_add_node('localhost', :master_port, groupId=>0); NOTICE: Replicating reference table "ref_table_test" to the node localhost:xxxxx ?column? --------------------------------------------------------------------- 1 (1 row) -- should just be noops even if we add the coordinator to the pg_dist_node SELECT rebalance_table_shards('dist_table_test'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT rebalance_table_shards(); rebalance_table_shards --------------------------------------------------------------------- (1 row) -- test that calling rebalance_table_shards without specifying relation -- wouldn't move shard of the citus local table. CREATE TABLE citus_local_table(a int, b int); SELECT create_citus_local_table('citus_local_table'); create_citus_local_table --------------------------------------------------------------------- (1 row) INSERT INTO citus_local_table VALUES (1, 2); SELECT rebalance_table_shards(); rebalance_table_shards --------------------------------------------------------------------- (1 row) -- show that citus local table shard is still on the coordinator SELECT tablename FROM pg_catalog.pg_tables where tablename like 'citus_local_table_%'; tablename --------------------------------------------------------------------- citus_local_table_102047 (1 row) -- also check that we still can access shard relation, not the shell table SELECT count(*) FROM citus_local_table; count --------------------------------------------------------------------- 1 (1 row) SELECT master_drain_node('localhost', :master_port); master_drain_node --------------------------------------------------------------------- (1 row) -- show that citus local table shard is still on the coordinator SELECT tablename FROM pg_catalog.pg_tables where tablename like 'citus_local_table_%'; tablename --------------------------------------------------------------------- citus_local_table_102047 (1 row) -- also check that we still can access shard relation, not the shell table SELECT count(*) FROM citus_local_table; count --------------------------------------------------------------------- 1 (1 row) -- show that we do not create a shard rebalancing plan for citus local table SELECT get_rebalance_table_shards_plan(); get_rebalance_table_shards_plan --------------------------------------------------------------------- (0 rows) DROP TABLE citus_local_table; CREATE TABLE dist_table_test_2(a int); SET citus.shard_count TO 4; SET citus.shard_replication_factor TO 1; SET citus.replication_model TO "statement"; SELECT create_distributed_table('dist_table_test_2', 'a'); create_distributed_table --------------------------------------------------------------------- (1 row) -- replicate reference table should ignore the coordinator SET citus.shard_replication_factor TO 2; SELECT replicate_table_shards('dist_table_test_2', max_shard_copies := 4, shard_transfer_mode:='block_writes'); NOTICE: Copying shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Copying shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Copying shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Copying shard xxxxx from localhost:xxxxx to localhost:xxxxx ... replicate_table_shards --------------------------------------------------------------------- (1 row) DROP TABLE dist_table_test, dist_table_test_2, ref_table_test; RESET citus.shard_count; RESET citus.shard_replication_factor; RESET citus.replication_model; -- Create a user to test multiuser usage of rebalancer functions CREATE USER testrole; NOTICE: not propagating CREATE ROLE/USER commands to worker nodes HINT: Connect to worker nodes directly to manually create all necessary users and roles. GRANT ALL ON SCHEMA public TO testrole; ERROR: role "testrole" does not exist CONTEXT: while executing command on localhost:xxxxx CREATE OR REPLACE FUNCTION shard_placement_rebalance_array( worker_node_list json[], shard_placement_list json[], threshold float4 DEFAULT 0, max_shard_moves int DEFAULT 1000000, drain_only bool DEFAULT false ) RETURNS json[] AS 'citus' LANGUAGE C STRICT VOLATILE; CREATE FUNCTION shard_placement_replication_array(worker_node_list json[], shard_placement_list json[], shard_replication_factor int) RETURNS json[] AS 'citus' LANGUAGE C STRICT VOLATILE; CREATE FUNCTION worker_node_responsive(worker_node_name text, worker_node_port int) RETURNS boolean AS 'citus' LANGUAGE C STRICT VOLATILE; -- this function is dropped in Citus10, added here for tests CREATE OR REPLACE FUNCTION pg_catalog.master_create_distributed_table(table_name regclass, distribution_column text, distribution_method citus.distribution_type) RETURNS void LANGUAGE C STRICT AS 'citus', $$master_create_distributed_table$$; COMMENT ON FUNCTION pg_catalog.master_create_distributed_table(table_name regclass, distribution_column text, distribution_method citus.distribution_type) IS 'define the table distribution functions'; -- this function is dropped in Citus10, added here for tests CREATE OR REPLACE FUNCTION pg_catalog.master_create_worker_shards(table_name text, shard_count integer, replication_factor integer DEFAULT 2) RETURNS void AS 'citus', $$master_create_worker_shards$$ LANGUAGE C STRICT; SET citus.next_shard_id TO 123000; SELECT worker_node_responsive(node_name, node_port::int) FROM master_get_active_worker_nodes() ORDER BY node_name, node_port ASC; worker_node_responsive --------------------------------------------------------------------- t t (2 rows) -- Check that worker_node_responsive returns false for dead nodes -- Note that PostgreSQL tries all possible resolutions of localhost on failing -- connections. This causes different error details to be printed on different -- environments. Therefore, we first set verbosity to terse. \set VERBOSITY terse SELECT worker_node_responsive('localhost', 1); worker_node_responsive --------------------------------------------------------------------- f (1 row) \set VERBOSITY default -- Check that with threshold=0.0 shard_placement_rebalance_array returns enough -- moves to make the cluster completely balanced. SELECT unnest(shard_placement_rebalance_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}', '{"node_name": "hostname2", "node_port": 5432}']::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":2, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":3, "shardid":3, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":4, "shardid":4, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":5, "shardid":5, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":6, "shardid":6, "shardstate":1, "shardlength":1, "nodename":"hostname2", "nodeport":5432}']::json[], 0.0 )); unnest --------------------------------------------------------------------- {"updatetype":1,"shardid":1,"sourcename":"hostname1","sourceport":5432,"targetname":"hostname2","targetport":5432} {"updatetype":1,"shardid":2,"sourcename":"hostname1","sourceport":5432,"targetname":"hostname2","targetport":5432} (2 rows) -- Check that with two nodes and threshold=1.0 shard_placement_rebalance_array -- doesn't return any moves, even if it is completely unbalanced. SELECT unnest(shard_placement_rebalance_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}', '{"node_name": "hostname2", "node_port": 5432}']::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":2, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":3, "shardid":3, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}']::json[], 1.0 )); unnest --------------------------------------------------------------------- (0 rows) -- Check that with three nodes and threshold=1.0 -- shard_placement_rebalance_array returns moves when it is completely unbalanced SELECT unnest(shard_placement_rebalance_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}', '{"node_name": "hostname2", "node_port": 5432}', '{"node_name": "hostname3", "node_port": 5432}' ]::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":2, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":3, "shardid":3, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}']::json[], 1.0 )); unnest --------------------------------------------------------------------- {"updatetype":1,"shardid":1,"sourcename":"hostname1","sourceport":5432,"targetname":"hostname2","targetport":5432} (1 row) -- Check that with with three nodes and threshold=2.0 -- shard_placement_rebalance_array doesn't return any moves, even if it is -- completely unbalanced. (with three nodes) SELECT unnest(shard_placement_rebalance_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}', '{"node_name": "hostname2", "node_port": 5432}', '{"node_name": "hostname3", "node_port": 5432}' ]::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":2, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":3, "shardid":3, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}']::json[], 2.0 )); unnest --------------------------------------------------------------------- (0 rows) -- Check that with threshold=0.0 shard_placement_rebalance_array doesn't return -- any moves if the cluster is already balanced. SELECT unnest(shard_placement_rebalance_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}', '{"node_name": "hostname2", "node_port": 5432}']::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":2, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":3, "shardid":3, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":4, "shardid":4, "shardstate":1, "shardlength":1, "nodename":"hostname2", "nodeport":5432}', '{"placementid":5, "shardid":5, "shardstate":1, "shardlength":1, "nodename":"hostname2", "nodeport":5432}', '{"placementid":6, "shardid":6, "shardstate":1, "shardlength":1, "nodename":"hostname2", "nodeport":5432}']::json[], 0.0 )); unnest --------------------------------------------------------------------- (0 rows) -- Check that shard_placement_replication_array returns a shard copy operation -- for each of the shards in an inactive node. SELECT unnest(shard_placement_replication_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}', '{"node_name": "hostname2", "node_port": 5432}']::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":2, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname2", "nodeport":5432}', '{"placementid":3, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname3", "nodeport":5432}', '{"placementid":4, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname3", "nodeport":5432}']::json[], 2 )); unnest --------------------------------------------------------------------- {"updatetype":2,"shardid":1,"sourcename":"hostname1","sourceport":5432,"targetname":"hostname2","targetport":5432} {"updatetype":2,"shardid":2,"sourcename":"hostname2","sourceport":5432,"targetname":"hostname1","targetport":5432} (2 rows) -- Check that shard_placement_replication_array returns a shard copy operation -- for each of the inactive shards. SELECT unnest(shard_placement_replication_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}', '{"node_name": "hostname2", "node_port": 5432}']::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":2, "shardid":2, "shardstate":3, "shardlength":1, "nodename":"hostname1", "nodeport":5432}', '{"placementid":3, "shardid":1, "shardstate":3, "shardlength":1, "nodename":"hostname2", "nodeport":5432}', '{"placementid":4, "shardid":2, "shardstate":1, "shardlength":1, "nodename":"hostname2", "nodeport":5432}']::json[], 2 )); unnest --------------------------------------------------------------------- {"updatetype":2,"shardid":1,"sourcename":"hostname1","sourceport":5432,"targetname":"hostname2","targetport":5432} {"updatetype":2,"shardid":2,"sourcename":"hostname2","sourceport":5432,"targetname":"hostname1","targetport":5432} (2 rows) -- Check that shard_placement_replication_array errors out if all placements of -- a shard are placed on inactive nodes. SELECT unnest(shard_placement_replication_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}']::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname2", "nodeport":5432}', '{"placementid":2, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname3", "nodeport":5432}']::json[], 2 )); ERROR: could not find a source for shard xxxxx -- Check that shard_placement_replication_array errors out if replication factor -- is more than number of active nodes. SELECT unnest(shard_placement_replication_array( ARRAY['{"node_name": "hostname1", "node_port": 5432}']::json[], ARRAY['{"placementid":1, "shardid":1, "shardstate":1, "shardlength":1, "nodename":"hostname1", "nodeport":5432}']::json[], 2 )); ERROR: could not find a target for shard xxxxx -- Ensure that shard_replication_factor is 2 during replicate_table_shards -- and rebalance_table_shards tests SET citus.shard_replication_factor TO 2; -- Turn off NOTICE messages SET client_min_messages TO WARNING; -- Create a single-row test data for shard rebalancer test shards CREATE TABLE shard_rebalancer_test_data AS SELECT 1::int as int_column; -- Test replicate_table_shards, which will in turn test update_shard_placement -- in copy mode. CREATE TABLE replication_test_table(int_column int); SELECT master_create_distributed_table('replication_test_table', 'int_column', 'append'); master_create_distributed_table --------------------------------------------------------------------- (1 row) CREATE VIEW replication_test_table_placements_per_node AS SELECT count(*) FROM pg_dist_shard_placement NATURAL JOIN pg_dist_shard WHERE logicalrelid = 'replication_test_table'::regclass GROUP BY nodename, nodeport ORDER BY nodename, nodeport; -- Create four shards with replication factor 2, and delete the placements -- with smaller port number to simulate under-replicated shards. SELECT count(master_create_empty_shard('replication_test_table')) FROM generate_series(1, 4); count --------------------------------------------------------------------- 4 (1 row) DELETE FROM pg_dist_shard_placement WHERE placementid in ( SELECT pg_dist_shard_placement.placementid FROM pg_dist_shard_placement NATURAL JOIN pg_dist_shard WHERE logicalrelid = 'replication_test_table'::regclass AND (nodename, nodeport) = (SELECT nodename, nodeport FROM pg_dist_shard_placement ORDER BY nodename, nodeport limit 1) ); -- Upload the test data to the shards SELECT count(master_append_table_to_shard(shardid, 'shard_rebalancer_test_data', host(inet_server_addr()), inet_server_port())) FROM pg_dist_shard WHERE logicalrelid = 'replication_test_table'::regclass; count --------------------------------------------------------------------- 4 (1 row) -- Verify that there is one node with all placements SELECT * FROM replication_test_table_placements_per_node; count --------------------------------------------------------------------- 4 (1 row) -- Check excluded_shard_list by excluding three shards with smaller ids SELECT replicate_table_shards('replication_test_table', excluded_shard_list := excluded_shard_list, shard_transfer_mode:='block_writes') FROM ( SELECT (array_agg(DISTINCT shardid ORDER BY shardid))[1:3] AS excluded_shard_list FROM pg_dist_shard WHERE logicalrelid = 'replication_test_table'::regclass ) T; replicate_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM replication_test_table_placements_per_node; count --------------------------------------------------------------------- 1 4 (2 rows) -- Check that with shard_replication_factor=1 we don't do any copies SELECT replicate_table_shards('replication_test_table', shard_replication_factor := 1, shard_transfer_mode:='block_writes'); replicate_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM replication_test_table_placements_per_node; count --------------------------------------------------------------------- 1 4 (2 rows) -- Check that max_shard_copies limits number of copy operations SELECT replicate_table_shards('replication_test_table', max_shard_copies := 2, shard_transfer_mode:='block_writes'); replicate_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM replication_test_table_placements_per_node; count --------------------------------------------------------------------- 3 4 (2 rows) -- Replicate the remaining under-replicated shards SELECT replicate_table_shards('replication_test_table'); replicate_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM replication_test_table_placements_per_node; count --------------------------------------------------------------------- 4 4 (2 rows) -- Check that querying the table doesn't error out SELECT count(*) FROM replication_test_table; count --------------------------------------------------------------------- 4 (1 row) DROP TABLE public.replication_test_table CASCADE; -- Test rebalance_table_shards, which will in turn test update_shard_placement -- in move mode. CREATE TABLE rebalance_test_table(int_column int); SELECT master_create_distributed_table('rebalance_test_table', 'int_column', 'append'); master_create_distributed_table --------------------------------------------------------------------- (1 row) CREATE VIEW table_placements_per_node AS SELECT nodeport, logicalrelid::regclass, count(*) FROM pg_dist_shard_placement NATURAL JOIN pg_dist_shard GROUP BY logicalrelid::regclass, nodename, nodeport ORDER BY logicalrelid::regclass, nodename, nodeport; -- Create six shards with replication factor 1 and move them to the same -- node to create an unbalanced cluster. CREATE PROCEDURE create_unbalanced_shards(rel text) LANGUAGE SQL AS $$ SET citus.shard_replication_factor TO 1; SELECT count(master_create_empty_shard(rel)) FROM generate_series(1, 6); SELECT count(master_move_shard_placement(shardid, src.nodename, src.nodeport::int, dst.nodename, dst.nodeport::int, shard_transfer_mode:='block_writes')) FROM pg_dist_shard s JOIN pg_dist_shard_placement src USING (shardid), (SELECT nodename, nodeport FROM pg_dist_shard_placement ORDER BY nodeport DESC LIMIT 1) dst WHERE src.nodeport < dst.nodeport AND s.logicalrelid = rel::regclass; $$; CALL create_unbalanced_shards('rebalance_test_table'); SET citus.shard_replication_factor TO 2; -- Upload the test data to the shards SELECT count(master_append_table_to_shard(shardid, 'shard_rebalancer_test_data', host(inet_server_addr()), inet_server_port())) FROM pg_dist_shard WHERE logicalrelid = 'rebalance_test_table'::regclass; count --------------------------------------------------------------------- 6 (1 row) -- Verify that there is one node with all placements SELECT * FROM table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57638 | rebalance_test_table | 6 (1 row) -- Check excluded_shard_list by excluding four shards with smaller ids SELECT rebalance_table_shards('rebalance_test_table', excluded_shard_list := excluded_shard_list, threshold := 0, shard_transfer_mode:='block_writes') FROM ( SELECT (array_agg(DISTINCT shardid ORDER BY shardid))[1:4] AS excluded_shard_list FROM pg_dist_shard WHERE logicalrelid = 'rebalance_test_table'::regclass ) T; rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | rebalance_test_table | 1 57638 | rebalance_test_table | 5 (2 rows) -- Check that max_shard_moves limits number of move operations -- First check that we error if not table owner SET ROLE testrole; SELECT rebalance_table_shards('rebalance_test_table', threshold := 0, max_shard_moves := 1, shard_transfer_mode:='block_writes'); WARNING: localhost:xxxxx is not responsive rebalance_table_shards --------------------------------------------------------------------- (1 row) RESET ROLE; SELECT rebalance_table_shards('rebalance_test_table', threshold := 0, max_shard_moves := 1, shard_transfer_mode:='block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | rebalance_test_table | 2 57638 | rebalance_test_table | 4 (2 rows) -- Check that threshold=1 doesn't move any shards SELECT rebalance_table_shards('rebalance_test_table', threshold := 1, shard_transfer_mode:='block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | rebalance_test_table | 2 57638 | rebalance_test_table | 4 (2 rows) -- Move the remaining shards using threshold=0 SELECT rebalance_table_shards('rebalance_test_table', threshold := 0); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | rebalance_test_table | 3 57638 | rebalance_test_table | 3 (2 rows) -- Check that shard is completely balanced and rebalancing again doesn't have -- any effects. SELECT rebalance_table_shards('rebalance_test_table', threshold := 0, shard_transfer_mode:='block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | rebalance_test_table | 3 57638 | rebalance_test_table | 3 (2 rows) -- Check that querying the table doesn't error out SELECT count(*) FROM rebalance_test_table; count --------------------------------------------------------------------- 6 (1 row) DROP TABLE rebalance_test_table; -- Test schema support CREATE SCHEMA test_schema_support; SELECT COUNT(*) FROM pg_dist_shard_placement; count --------------------------------------------------------------------- 0 (1 row) CREATE TABLE test_schema_support.nation_hash ( n_nationkey integer not null, n_name char(25) not null, n_regionkey integer not null, n_comment varchar(152) ); SELECT master_create_distributed_table('test_schema_support.nation_hash', 'n_nationkey', 'hash'); master_create_distributed_table --------------------------------------------------------------------- (1 row) SELECT master_create_worker_shards('test_schema_support.nation_hash', 4, 1); master_create_worker_shards --------------------------------------------------------------------- (1 row) CREATE TABLE test_schema_support.nation_hash2 ( n_nationkey integer not null, n_name char(25) not null, n_regionkey integer not null, n_comment varchar(152) ); SELECT master_create_distributed_table('test_schema_support.nation_hash2', 'n_nationkey', 'hash'); master_create_distributed_table --------------------------------------------------------------------- (1 row) SELECT master_create_worker_shards('test_schema_support.nation_hash2', 4, 1); master_create_worker_shards --------------------------------------------------------------------- (1 row) -- Shard count before replication SELECT COUNT(*) FROM pg_dist_shard_placement; count --------------------------------------------------------------------- 8 (1 row) SET search_path TO public; SELECT replicate_table_shards('test_schema_support.nation_hash', shard_transfer_mode:='block_writes'); replicate_table_shards --------------------------------------------------------------------- (1 row) -- Confirm replication SELECT COUNT(*) FROM pg_dist_shard_placement; count --------------------------------------------------------------------- 12 (1 row) -- Test with search_path is set SET search_path TO test_schema_support; SELECT replicate_table_shards('nation_hash2', shard_transfer_mode:='block_writes'); replicate_table_shards --------------------------------------------------------------------- (1 row) -- Confirm replication SELECT COUNT(*) FROM pg_dist_shard_placement; count --------------------------------------------------------------------- 16 (1 row) DROP TABLE test_schema_support.nation_hash; DROP TABLE test_schema_support.nation_hash2; -- Test rebalancer with schema -- Next few operations is to create imbalanced distributed table CREATE TABLE test_schema_support.imbalanced_table_local ( id integer not null ); INSERT INTO test_schema_support.imbalanced_table_local VALUES(1); INSERT INTO test_schema_support.imbalanced_table_local VALUES(2); INSERT INTO test_schema_support.imbalanced_table_local VALUES(3); INSERT INTO test_schema_support.imbalanced_table_local VALUES(4); CREATE TABLE test_schema_support.imbalanced_table ( id integer not null ); SELECT master_create_distributed_table('test_schema_support.imbalanced_table', 'id', 'append'); master_create_distributed_table --------------------------------------------------------------------- (1 row) SET citus.shard_replication_factor TO 1; SELECT * from master_create_empty_shard('test_schema_support.imbalanced_table'); master_create_empty_shard --------------------------------------------------------------------- 123018 (1 row) SELECT master_append_table_to_shard(123018, 'test_schema_support.imbalanced_table_local', 'localhost', :master_port); master_append_table_to_shard --------------------------------------------------------------------- 0.00533333 (1 row) SET citus.shard_replication_factor TO 2; SELECT * from master_create_empty_shard('test_schema_support.imbalanced_table'); master_create_empty_shard --------------------------------------------------------------------- 123019 (1 row) SELECT master_append_table_to_shard(123019, 'test_schema_support.imbalanced_table_local', 'localhost', :master_port); master_append_table_to_shard --------------------------------------------------------------------- 0.00533333 (1 row) SET citus.shard_replication_factor TO 1; SELECT * from master_create_empty_shard('test_schema_support.imbalanced_table'); master_create_empty_shard --------------------------------------------------------------------- 123020 (1 row) SELECT master_append_table_to_shard(123020, 'test_schema_support.imbalanced_table_local', 'localhost', :master_port); master_append_table_to_shard --------------------------------------------------------------------- 0.00533333 (1 row) -- imbalanced_table is now imbalanced -- Shard counts in each node before rebalance SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | imbalanced_table | 1 57638 | imbalanced_table | 3 (2 rows) -- Row count in imbalanced table before rebalance SELECT COUNT(*) FROM imbalanced_table; count --------------------------------------------------------------------- 12 (1 row) -- Try force_logical SELECT rebalance_table_shards('imbalanced_table', threshold:=0, shard_transfer_mode:='force_logical'); ERROR: the force_logical transfer mode is currently unsupported -- Test rebalance operation SELECT rebalance_table_shards('imbalanced_table', threshold:=0, shard_transfer_mode:='block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) -- Confirm rebalance -- Shard counts in each node after rebalance SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | imbalanced_table | 2 57638 | imbalanced_table | 2 (2 rows) -- Row count in imbalanced table after rebalance SELECT COUNT(*) FROM imbalanced_table; count --------------------------------------------------------------------- 12 (1 row) DROP TABLE public.shard_rebalancer_test_data; DROP TABLE test_schema_support.imbalanced_table; DROP TABLE test_schema_support.imbalanced_table_local; SET citus.shard_replication_factor TO 1; CREATE TABLE colocated_rebalance_test(id integer); CREATE TABLE colocated_rebalance_test2(id integer); SELECT create_distributed_table('colocated_rebalance_test', 'id'); create_distributed_table --------------------------------------------------------------------- (1 row) -- Move all shards to worker1 SELECT master_move_shard_placement(shardid, 'localhost', :worker_2_port, 'localhost', :worker_1_port, 'block_writes') FROM pg_dist_shard_placement WHERE nodeport = :worker_2_port; master_move_shard_placement --------------------------------------------------------------------- (2 rows) SELECT create_distributed_table('colocated_rebalance_test2', 'id'); create_distributed_table --------------------------------------------------------------------- (1 row) -- Confirm all shards for both tables are on worker1 SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 4 57637 | colocated_rebalance_test2 | 4 (2 rows) -- Confirm that the plan for drain_only doesn't show any moves SELECT * FROM get_rebalance_table_shards_plan('colocated_rebalance_test', threshold := 0, drain_only := true); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- (0 rows) -- Running with drain_only shouldn't do anything SELECT * FROM rebalance_table_shards('colocated_rebalance_test', threshold := 0, shard_transfer_mode := 'block_writes', drain_only := true); rebalance_table_shards --------------------------------------------------------------------- (1 row) -- Confirm that nothing changed SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 4 57637 | colocated_rebalance_test2 | 4 (2 rows) -- Confirm that the plan shows 2 shards of both tables moving back to worker2 SELECT * FROM get_rebalance_table_shards_plan('colocated_rebalance_test', threshold := 0); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- colocated_rebalance_test | 123021 | 0 | localhost | 57637 | localhost | 57638 colocated_rebalance_test2 | 123025 | 0 | localhost | 57637 | localhost | 57638 colocated_rebalance_test | 123022 | 0 | localhost | 57637 | localhost | 57638 colocated_rebalance_test2 | 123026 | 0 | localhost | 57637 | localhost | 57638 (4 rows) -- Confirm that this also happens when using rebalancing by disk size even if the tables are empty SELECT * FROM get_rebalance_table_shards_plan('colocated_rebalance_test', rebalance_strategy := 'by_disk_size'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- colocated_rebalance_test | 123021 | 0 | localhost | 57637 | localhost | 57638 colocated_rebalance_test2 | 123025 | 0 | localhost | 57637 | localhost | 57638 colocated_rebalance_test | 123022 | 0 | localhost | 57637 | localhost | 57638 colocated_rebalance_test2 | 123026 | 0 | localhost | 57637 | localhost | 57638 (4 rows) -- Check that we can call this function SELECT * FROM get_rebalance_progress(); sessionid | table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport | progress --------------------------------------------------------------------- (0 rows) -- Actually do the rebalance SELECT * FROM rebalance_table_shards('colocated_rebalance_test', threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) -- Check that we can call this function without a crash SELECT * FROM get_rebalance_progress(); sessionid | table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport | progress --------------------------------------------------------------------- (0 rows) -- Confirm that the nodes are now there SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 2 57638 | colocated_rebalance_test | 2 57637 | colocated_rebalance_test2 | 2 57638 | colocated_rebalance_test2 | 2 (4 rows) CREATE TABLE non_colocated_rebalance_test(id integer); SELECT create_distributed_table('non_colocated_rebalance_test', 'id', colocate_with := 'none'); create_distributed_table --------------------------------------------------------------------- (1 row) -- confirm that both colocation groups are balanced SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 2 57638 | colocated_rebalance_test | 2 57637 | colocated_rebalance_test2 | 2 57638 | colocated_rebalance_test2 | 2 57637 | non_colocated_rebalance_test | 2 57638 | non_colocated_rebalance_test | 2 (6 rows) -- testing behaviour when setting isdatanode to 'marked for draining' SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', false); master_set_node_property --------------------------------------------------------------------- (1 row) SELECT * FROM get_rebalance_table_shards_plan('colocated_rebalance_test', threshold := 0); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- colocated_rebalance_test | 123021 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test2 | 123025 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test | 123022 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test2 | 123026 | 0 | localhost | 57638 | localhost | 57637 (4 rows) SELECT * FROM rebalance_table_shards('colocated_rebalance_test', threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 4 57637 | colocated_rebalance_test2 | 4 57637 | non_colocated_rebalance_test | 2 57638 | non_colocated_rebalance_test | 2 (4 rows) SELECT * FROM get_rebalance_table_shards_plan('non_colocated_rebalance_test', threshold := 0); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- non_colocated_rebalance_test | 123030 | 0 | localhost | 57638 | localhost | 57637 non_colocated_rebalance_test | 123032 | 0 | localhost | 57638 | localhost | 57637 (2 rows) SELECT * FROM rebalance_table_shards('non_colocated_rebalance_test', threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 4 57637 | colocated_rebalance_test2 | 4 57637 | non_colocated_rebalance_test | 4 (3 rows) -- Put shards back SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', true); master_set_node_property --------------------------------------------------------------------- (1 row) SELECT * FROM rebalance_table_shards('colocated_rebalance_test', threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 2 57638 | colocated_rebalance_test | 2 57637 | colocated_rebalance_test2 | 2 57638 | colocated_rebalance_test2 | 2 57637 | non_colocated_rebalance_test | 4 (5 rows) SELECT * FROM rebalance_table_shards('non_colocated_rebalance_test', threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 2 57638 | colocated_rebalance_test | 2 57637 | colocated_rebalance_test2 | 2 57638 | colocated_rebalance_test2 | 2 57637 | non_colocated_rebalance_test | 2 57638 | non_colocated_rebalance_test | 2 (6 rows) -- testing behaviour when setting shouldhaveshards to false and rebalancing all -- colocation groups with drain_only=true SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', false); master_set_node_property --------------------------------------------------------------------- (1 row) SELECT * FROM get_rebalance_table_shards_plan(threshold := 0, drain_only := true); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- colocated_rebalance_test | 123021 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test2 | 123025 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test | 123022 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test2 | 123026 | 0 | localhost | 57638 | localhost | 57637 non_colocated_rebalance_test | 123029 | 0 | localhost | 57638 | localhost | 57637 non_colocated_rebalance_test | 123030 | 0 | localhost | 57638 | localhost | 57637 (6 rows) SELECT * FROM rebalance_table_shards(threshold := 0, shard_transfer_mode := 'block_writes', drain_only := true); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 4 57637 | colocated_rebalance_test2 | 4 57637 | non_colocated_rebalance_test | 4 (3 rows) -- Put shards back SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', true); master_set_node_property --------------------------------------------------------------------- (1 row) SELECT * FROM rebalance_table_shards(threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 2 57638 | colocated_rebalance_test | 2 57637 | colocated_rebalance_test2 | 2 57638 | colocated_rebalance_test2 | 2 57637 | non_colocated_rebalance_test | 2 57638 | non_colocated_rebalance_test | 2 (6 rows) -- testing behaviour when setting shouldhaveshards to false and rebalancing all -- colocation groups with drain_only=false SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', false); master_set_node_property --------------------------------------------------------------------- (1 row) SELECT * FROM get_rebalance_table_shards_plan(threshold := 0); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- colocated_rebalance_test | 123021 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test2 | 123025 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test | 123022 | 0 | localhost | 57638 | localhost | 57637 colocated_rebalance_test2 | 123026 | 0 | localhost | 57638 | localhost | 57637 non_colocated_rebalance_test | 123029 | 0 | localhost | 57638 | localhost | 57637 non_colocated_rebalance_test | 123030 | 0 | localhost | 57638 | localhost | 57637 (6 rows) SELECT * FROM rebalance_table_shards(threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 4 57637 | colocated_rebalance_test2 | 4 57637 | non_colocated_rebalance_test | 4 (3 rows) -- Put shards back SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', true); master_set_node_property --------------------------------------------------------------------- (1 row) SELECT * FROM rebalance_table_shards(threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 2 57638 | colocated_rebalance_test | 2 57637 | colocated_rebalance_test2 | 2 57638 | colocated_rebalance_test2 | 2 57637 | non_colocated_rebalance_test | 2 57638 | non_colocated_rebalance_test | 2 (6 rows) -- Make it a data node again SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', true); master_set_node_property --------------------------------------------------------------------- (1 row) -- testing behaviour of master_drain_node SELECT * from master_drain_node('localhost', :worker_2_port, shard_transfer_mode := 'block_writes'); master_drain_node --------------------------------------------------------------------- (1 row) select shouldhaveshards from pg_dist_node where nodeport = :worker_2_port; shouldhaveshards --------------------------------------------------------------------- f (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 4 57637 | colocated_rebalance_test2 | 4 57637 | non_colocated_rebalance_test | 4 (3 rows) -- Put shards back SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', true); master_set_node_property --------------------------------------------------------------------- (1 row) SELECT * FROM rebalance_table_shards(threshold := 0, shard_transfer_mode := 'block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | colocated_rebalance_test | 2 57638 | colocated_rebalance_test | 2 57637 | colocated_rebalance_test2 | 2 57638 | colocated_rebalance_test2 | 2 57637 | non_colocated_rebalance_test | 2 57638 | non_colocated_rebalance_test | 2 (6 rows) -- Drop some tables for clear consistent error DROP TABLE test_schema_support.colocated_rebalance_test2; -- Leave no trace on workers RESET search_path; \set VERBOSITY terse DROP SCHEMA test_schema_support CASCADE; \set VERBOSITY default REVOKE ALL ON SCHEMA public FROM testrole; ERROR: role "testrole" does not exist CONTEXT: while executing command on localhost:xxxxx DROP USER testrole; -- Test costs set citus.shard_count = 4; CREATE TABLE tab (x int); SELECT create_distributed_table('tab','x'); create_distributed_table --------------------------------------------------------------------- (1 row) -- The following numbers are chosen such that they are placed on different -- shards. INSERT INTO tab SELECT 1 from generate_series(1, 30000); INSERT INTO tab SELECT 2 from generate_series(1, 10000); INSERT INTO tab SELECT 3 from generate_series(1, 10000); INSERT INTO tab SELECT 6 from generate_series(1, 10000); ANALYZE tab; \c - - - :worker_1_port SELECT table_schema, table_name, row_estimate, total_bytes FROM ( SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM ( SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME , c.reltuples AS row_estimate , pg_total_relation_size(c.oid) AS total_bytes , pg_indexes_size(c.oid) AS index_bytes , pg_total_relation_size(reltoastrelid) AS toast_bytes FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE relkind = 'r' ) a WHERE table_schema = 'public' ) a ORDER BY table_name; table_schema | table_name | row_estimate | total_bytes --------------------------------------------------------------------- public | tab_123033 | 30000 | 1114112 public | tab_123035 | 10000 | 393216 (2 rows) \c - - - :worker_2_port SELECT table_schema, table_name, row_estimate, total_bytes FROM ( SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM ( SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME , c.reltuples AS row_estimate , pg_total_relation_size(c.oid) AS total_bytes , pg_indexes_size(c.oid) AS index_bytes , pg_total_relation_size(reltoastrelid) AS toast_bytes FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE relkind = 'r' ) a WHERE table_schema = 'public' ) a ORDER BY table_name; table_schema | table_name | row_estimate | total_bytes --------------------------------------------------------------------- public | tab_123034 | 10000 | 393216 public | tab_123036 | 10000 | 393216 (2 rows) \c - - - :master_port SELECT * FROM get_rebalance_table_shards_plan('tab'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- (0 rows) SELECT * FROM get_rebalance_table_shards_plan('tab', rebalance_strategy := 'by_disk_size'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- tab | 123035 | 0 | localhost | 57637 | localhost | 57638 (1 row) SELECT * FROM get_rebalance_table_shards_plan('tab', rebalance_strategy := 'by_disk_size', threshold := 0); WARNING: the given threshold is lower than the minimum threshold allowed by the rebalance strategy, using the minimum allowed threshold instead DETAIL: Using threshold of 0.01 table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- tab | 123035 | 0 | localhost | 57637 | localhost | 57638 (1 row) SELECT * FROM rebalance_table_shards('tab', shard_transfer_mode:='block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | tab | 2 57638 | tab | 2 (2 rows) SELECT * FROM rebalance_table_shards('tab', rebalance_strategy := 'by_disk_size', shard_transfer_mode:='block_writes'); NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | tab | 1 57638 | tab | 3 (2 rows) SELECT * FROM rebalance_table_shards('tab', rebalance_strategy := 'by_disk_size', shard_transfer_mode:='block_writes', threshold := 0); WARNING: the given threshold is lower than the minimum threshold allowed by the rebalance strategy, using the minimum allowed threshold instead DETAIL: Using threshold of 0.01 rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | tab | 1 57638 | tab | 3 (2 rows) -- Check that sizes of colocated tables are added together for rebalances set citus.shard_count = 4; SET citus.next_shard_id TO 123050; CREATE TABLE tab2 (x int); SELECT create_distributed_table('tab2','x', colocate_with := 'tab'); create_distributed_table --------------------------------------------------------------------- (1 row) INSERT INTO tab2 SELECT 1 from generate_series(1, 0); INSERT INTO tab2 SELECT 2 from generate_series(1, 60000); INSERT INTO tab2 SELECT 3 from generate_series(1, 10000); INSERT INTO tab2 SELECT 6 from generate_series(1, 10000); ANALYZE tab, tab2; \c - - - :worker_1_port SELECT table_schema, table_name, row_estimate, total_bytes FROM ( SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM ( SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME , c.reltuples AS row_estimate , pg_total_relation_size(c.oid) AS total_bytes , pg_indexes_size(c.oid) AS index_bytes , pg_total_relation_size(reltoastrelid) AS toast_bytes FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE relkind = 'r' ) a WHERE table_schema = 'public' ) a ORDER BY table_name; table_schema | table_name | row_estimate | total_bytes --------------------------------------------------------------------- public | tab2_123050 | 0 | 0 public | tab_123033 | 30000 | 1114112 (2 rows) \c - - - :worker_2_port SELECT table_schema, table_name, row_estimate, total_bytes FROM ( SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM ( SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME , c.reltuples AS row_estimate , pg_total_relation_size(c.oid) AS total_bytes , pg_indexes_size(c.oid) AS index_bytes , pg_total_relation_size(reltoastrelid) AS toast_bytes FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE relkind = 'r' ) a WHERE table_schema = 'public' ) a ORDER BY table_name; table_schema | table_name | row_estimate | total_bytes --------------------------------------------------------------------- public | tab2_123051 | 10000 | 393216 public | tab2_123052 | 10000 | 393216 public | tab2_123053 | 60000 | 2203648 public | tab_123034 | 10000 | 393216 public | tab_123035 | 10000 | 368640 public | tab_123036 | 10000 | 393216 (6 rows) \c - - - :master_port SELECT * FROM get_rebalance_table_shards_plan('tab', rebalance_strategy := 'by_disk_size'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- tab | 123036 | 0 | localhost | 57638 | localhost | 57637 tab2 | 123053 | 0 | localhost | 57638 | localhost | 57637 tab | 123033 | 0 | localhost | 57637 | localhost | 57638 tab2 | 123050 | 0 | localhost | 57637 | localhost | 57638 (4 rows) SELECT * FROM rebalance_table_shards('tab', rebalance_strategy := 'by_disk_size', shard_transfer_mode:='block_writes'); NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | tab | 1 57638 | tab | 3 57637 | tab2 | 1 57638 | tab2 | 3 (4 rows) ANALYZE tab, tab2; \c - - - :worker_1_port SELECT table_schema, table_name, row_estimate, total_bytes FROM ( SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM ( SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME , c.reltuples AS row_estimate , pg_total_relation_size(c.oid) AS total_bytes , pg_indexes_size(c.oid) AS index_bytes , pg_total_relation_size(reltoastrelid) AS toast_bytes FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE relkind = 'r' ) a WHERE table_schema = 'public' ) a ORDER BY table_name; table_schema | table_name | row_estimate | total_bytes --------------------------------------------------------------------- public | tab2_123053 | 60000 | 2179072 public | tab_123036 | 10000 | 368640 (2 rows) \c - - - :worker_2_port SELECT table_schema, table_name, row_estimate, total_bytes FROM ( SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM ( SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME , c.reltuples AS row_estimate , pg_total_relation_size(c.oid) AS total_bytes , pg_indexes_size(c.oid) AS index_bytes , pg_total_relation_size(reltoastrelid) AS toast_bytes FROM pg_class c LEFT JOIN pg_namespace n ON n.oid = c.relnamespace WHERE relkind = 'r' ) a WHERE table_schema = 'public' ) a ORDER BY table_name; table_schema | table_name | row_estimate | total_bytes --------------------------------------------------------------------- public | tab2_123050 | 0 | 0 public | tab2_123051 | 10000 | 393216 public | tab2_123052 | 10000 | 393216 public | tab_123033 | 30000 | 1089536 public | tab_123034 | 10000 | 393216 public | tab_123035 | 10000 | 368640 (6 rows) \c - - - :master_port DROP TABLE tab2; CREATE OR REPLACE FUNCTION capacity_high_worker_1(nodeidarg int) RETURNS real AS $$ SELECT (CASE WHEN nodeport = 57637 THEN 1000 ELSE 1 END)::real FROM pg_dist_node where nodeid = nodeidarg $$ LANGUAGE sql; SELECT citus_add_rebalance_strategy( 'capacity_high_worker_1', 'citus_shard_cost_1', 'capacity_high_worker_1', 'citus_shard_allowed_on_node_true', 0 ); citus_add_rebalance_strategy --------------------------------------------------------------------- (1 row) SELECT * FROM get_rebalance_table_shards_plan('tab', rebalance_strategy := 'capacity_high_worker_1'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- tab | 123033 | 0 | localhost | 57638 | localhost | 57637 tab | 123034 | 0 | localhost | 57638 | localhost | 57637 tab | 123035 | 0 | localhost | 57638 | localhost | 57637 (3 rows) SELECT * FROM rebalance_table_shards('tab', rebalance_strategy := 'capacity_high_worker_1', shard_transfer_mode:='block_writes'); NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | tab | 4 (1 row) SELECT citus_set_default_rebalance_strategy('capacity_high_worker_1'); citus_set_default_rebalance_strategy --------------------------------------------------------------------- (1 row) SELECT * FROM get_rebalance_table_shards_plan('tab'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- (0 rows) SELECT * FROM rebalance_table_shards('tab', shard_transfer_mode:='block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57637 | tab | 4 (1 row) CREATE FUNCTION only_worker_2(shardid bigint, nodeidarg int) RETURNS boolean AS $$ SELECT (CASE WHEN nodeport = 57638 THEN TRUE ELSE FALSE END) FROM pg_dist_node where nodeid = nodeidarg $$ LANGUAGE sql; SELECT citus_add_rebalance_strategy( 'only_worker_2', 'citus_shard_cost_1', 'citus_node_capacity_1', 'only_worker_2', 0 ); citus_add_rebalance_strategy --------------------------------------------------------------------- (1 row) SELECT citus_set_default_rebalance_strategy('only_worker_2'); citus_set_default_rebalance_strategy --------------------------------------------------------------------- (1 row) SELECT * FROM get_rebalance_table_shards_plan('tab'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- tab | 123033 | 0 | localhost | 57637 | localhost | 57638 tab | 123034 | 0 | localhost | 57637 | localhost | 57638 tab | 123035 | 0 | localhost | 57637 | localhost | 57638 tab | 123036 | 0 | localhost | 57637 | localhost | 57638 (4 rows) SELECT * FROM rebalance_table_shards('tab', shard_transfer_mode:='block_writes'); NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... NOTICE: Moving shard xxxxx from localhost:xxxxx to localhost:xxxxx ... rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT * FROM public.table_placements_per_node; nodeport | logicalrelid | count --------------------------------------------------------------------- 57638 | tab | 4 (1 row) SELECT citus_set_default_rebalance_strategy('by_shard_count'); citus_set_default_rebalance_strategy --------------------------------------------------------------------- (1 row) SELECT * FROM get_rebalance_table_shards_plan('tab'); table_name | shardid | shard_size | sourcename | sourceport | targetname | targetport --------------------------------------------------------------------- tab | 123033 | 0 | localhost | 57638 | localhost | 57637 tab | 123034 | 0 | localhost | 57638 | localhost | 57637 (2 rows) -- Check all the error handling cases SELECT * FROM get_rebalance_table_shards_plan('tab', rebalance_strategy := 'non_existing'); ERROR: could not find rebalance strategy with name non_existing SELECT * FROM rebalance_table_shards('tab', rebalance_strategy := 'non_existing'); ERROR: could not find rebalance strategy with name non_existing SELECT * FROM master_drain_node('localhost', :worker_2_port, rebalance_strategy := 'non_existing'); ERROR: could not find rebalance strategy with name non_existing SELECT citus_set_default_rebalance_strategy('non_existing'); ERROR: strategy with specified name does not exist CONTEXT: PL/pgSQL function citus_set_default_rebalance_strategy(text) line 5 at RAISE UPDATE pg_dist_rebalance_strategy SET default_strategy=false; SELECT * FROM get_rebalance_table_shards_plan('tab'); ERROR: no rebalance_strategy was provided, but there is also no default strategy set SELECT * FROM rebalance_table_shards('tab'); ERROR: no rebalance_strategy was provided, but there is also no default strategy set SELECT * FROM master_drain_node('localhost', :worker_2_port); ERROR: no rebalance_strategy was provided, but there is also no default strategy set UPDATE pg_dist_rebalance_strategy SET default_strategy=true WHERE name='by_shard_count'; CREATE OR REPLACE FUNCTION shard_cost_no_arguments() RETURNS real AS $$ SELECT 1.0::real $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION shard_cost_bad_arg_type(text) RETURNS real AS $$ SELECT 1.0::real $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION shard_cost_bad_return_type(bigint) RETURNS int AS $$ SELECT 1 $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION node_capacity_no_arguments() RETURNS real AS $$ SELECT 1.0::real $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION node_capacity_bad_arg_type(text) RETURNS real AS $$ SELECT 1.0::real $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION node_capacity_bad_return_type(int) RETURNS int AS $$ SELECT 1 $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION shard_allowed_on_node_no_arguments() RETURNS boolean AS $$ SELECT true $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION shard_allowed_on_node_bad_arg1(text, int) RETURNS boolean AS $$ SELECT true $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION shard_allowed_on_node_bad_arg2(bigint, text) RETURNS boolean AS $$ SELECT true $$ LANGUAGE sql; CREATE OR REPLACE FUNCTION shard_allowed_on_node_bad_return_type(bigint, int) RETURNS int AS $$ SELECT 1 $$ LANGUAGE sql; SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'shard_cost_no_arguments', 'citus_node_capacity_1', 'citus_shard_allowed_on_node_true', 0 ); ERROR: signature for shard_cost_function is incorrect DETAIL: number of arguments of shard_cost_no_arguments should be 1, not 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'shard_cost_bad_arg_type', 'citus_node_capacity_1', 'citus_shard_allowed_on_node_true', 0 ); ERROR: signature for shard_cost_function is incorrect DETAIL: argument type of shard_cost_bad_arg_type should be bigint CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'shard_cost_bad_return_type', 'citus_node_capacity_1', 'citus_shard_allowed_on_node_true', 0 ); ERROR: signature for shard_cost_function is incorrect DETAIL: return type of shard_cost_bad_return_type should be real CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 0, 'citus_node_capacity_1', 'citus_shard_allowed_on_node_true', 0 ); ERROR: cache lookup failed for shard_cost_function with oid 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'node_capacity_no_arguments', 'citus_shard_allowed_on_node_true', 0 ); ERROR: signature for node_capacity_function is incorrect DETAIL: number of arguments of node_capacity_no_arguments should be 1, not 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'node_capacity_bad_arg_type', 'citus_shard_allowed_on_node_true', 0 ); ERROR: signature for node_capacity_function is incorrect DETAIL: argument type of node_capacity_bad_arg_type should be int CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'node_capacity_bad_return_type', 'citus_shard_allowed_on_node_true', 0 ); ERROR: signature for node_capacity_function is incorrect DETAIL: return type of node_capacity_bad_return_type should be real CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 0, 'citus_shard_allowed_on_node_true', 0 ); ERROR: cache lookup failed for node_capacity_function with oid 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'citus_node_capacity_1', 'shard_allowed_on_node_no_arguments', 0 ); ERROR: signature for shard_allowed_on_node_function is incorrect DETAIL: number of arguments of shard_allowed_on_node_no_arguments should be 2, not 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'citus_node_capacity_1', 'shard_allowed_on_node_bad_arg1', 0 ); ERROR: signature for shard_allowed_on_node_function is incorrect DETAIL: type of first argument of shard_allowed_on_node_bad_arg1 should be bigint CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'citus_node_capacity_1', 'shard_allowed_on_node_bad_arg2', 0 ); ERROR: signature for shard_allowed_on_node_function is incorrect DETAIL: type of second argument of shard_allowed_on_node_bad_arg2 should be int CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'citus_node_capacity_1', 'shard_allowed_on_node_bad_return_type', 0 ); ERROR: signature for shard_allowed_on_node_function is incorrect DETAIL: return type of shard_allowed_on_node_bad_return_type should be boolean CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 SELECT citus_add_rebalance_strategy( 'insert_should_fail', 'citus_shard_cost_1', 'citus_node_capacity_1', 0, 0 ); ERROR: cache lookup failed for shard_allowed_on_node_function with oid 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM SQL function "citus_add_rebalance_strategy" statement 1 -- Confirm that manual insert/update has the same checks INSERT INTO pg_catalog.pg_dist_rebalance_strategy( name, shard_cost_function, node_capacity_function, shard_allowed_on_node_function, default_threshold ) VALUES ( 'shard_cost_no_arguments', 'shard_cost_no_arguments', 'citus_node_capacity_1', 'citus_shard_allowed_on_node_true', 0 ); ERROR: signature for shard_cost_function is incorrect DETAIL: number of arguments of shard_cost_no_arguments should be 1, not 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM UPDATE pg_dist_rebalance_strategy SET shard_cost_function='shard_cost_no_arguments' WHERE name='by_disk_size'; ERROR: signature for shard_cost_function is incorrect DETAIL: number of arguments of shard_cost_no_arguments should be 1, not 0 CONTEXT: SQL statement "SELECT citus_validate_rebalance_strategy_functions( NEW.shard_cost_function, NEW.node_capacity_function, NEW.shard_allowed_on_node_function)" PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 5 at PERFORM -- Confirm that only a single default strategy can exist INSERT INTO pg_catalog.pg_dist_rebalance_strategy( name, default_strategy, shard_cost_function, node_capacity_function, shard_allowed_on_node_function, default_threshold ) VALUES ( 'second_default', true, 'citus_shard_cost_1', 'citus_node_capacity_1', 'citus_shard_allowed_on_node_true', 0 ); ERROR: there cannot be two default strategies CONTEXT: PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 19 at RAISE UPDATE pg_dist_rebalance_strategy SET default_strategy=true WHERE name='by_disk_size'; ERROR: there cannot be two default strategies CONTEXT: PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 19 at RAISE -- ensure the trigger allows updating the default strategy UPDATE pg_dist_rebalance_strategy SET default_strategy=true WHERE name='by_shard_count'; -- Confirm that default strategy should be higher than minimum strategy SELECT citus_add_rebalance_strategy( 'default_threshold_too_low', 'citus_shard_cost_1', 'capacity_high_worker_1', 'citus_shard_allowed_on_node_true', 0, 0.1 ); ERROR: default_threshold cannot be smaller than minimum_threshold CONTEXT: PL/pgSQL function citus_internal.pg_dist_rebalance_strategy_trigger_func() line 10 at RAISE SQL function "citus_add_rebalance_strategy" statement 1 -- Make it a data node again SELECT * from master_set_node_property('localhost', :worker_2_port, 'shouldhaveshards', true); master_set_node_property --------------------------------------------------------------------- (1 row) DROP TABLE tab; -- we don't need the coordinator on pg_dist_node anymore SELECT 1 FROM master_remove_node('localhost', :master_port); ?column? --------------------------------------------------------------------- 1 (1 row) -- -- Make sure that rebalance_table_shards() and replicate_table_shards() replicate -- reference tables to the coordinator when replicate_reference_tables_on_activate -- is off. -- SET citus.replicate_reference_tables_on_activate TO off; SET client_min_messages TO WARNING; CREATE TABLE dist_table_test_3(a int); SET citus.shard_count TO 4; SET citus.shard_replication_factor TO 1; SET citus.replication_model TO "statement"; SELECT create_distributed_table('dist_table_test_3', 'a'); create_distributed_table --------------------------------------------------------------------- (1 row) CREATE TABLE ref_table(a int); SELECT create_reference_table('ref_table'); create_reference_table --------------------------------------------------------------------- (1 row) SELECT 1 FROM master_add_node('localhost', :master_port, groupId=>0); ?column? --------------------------------------------------------------------- 1 (1 row) SELECT count(*) FROM pg_dist_shard NATURAL JOIN pg_dist_shard_placement WHERE logicalrelid = 'ref_table'::regclass; count --------------------------------------------------------------------- 2 (1 row) SET citus.shard_replication_factor TO 2; SELECT replicate_table_shards('dist_table_test_3', max_shard_copies := 4, shard_transfer_mode:='block_writes'); replicate_table_shards --------------------------------------------------------------------- (1 row) SELECT count(*) FROM pg_dist_shard NATURAL JOIN pg_dist_shard_placement WHERE logicalrelid = 'ref_table'::regclass; count --------------------------------------------------------------------- 3 (1 row) SELECT 1 FROM master_remove_node('localhost', :master_port); ?column? --------------------------------------------------------------------- 1 (1 row) CREATE TABLE rebalance_test_table(int_column int); SELECT master_create_distributed_table('rebalance_test_table', 'int_column', 'append'); master_create_distributed_table --------------------------------------------------------------------- (1 row) CALL create_unbalanced_shards('rebalance_test_table'); SELECT 1 FROM master_add_node('localhost', :master_port, groupId=>0); ?column? --------------------------------------------------------------------- 1 (1 row) SELECT count(*) FROM pg_dist_shard NATURAL JOIN pg_dist_shard_placement WHERE logicalrelid = 'ref_table'::regclass; count --------------------------------------------------------------------- 2 (1 row) SELECT rebalance_table_shards('rebalance_test_table', shard_transfer_mode:='block_writes'); rebalance_table_shards --------------------------------------------------------------------- (1 row) SELECT count(*) FROM pg_dist_shard NATURAL JOIN pg_dist_shard_placement WHERE logicalrelid = 'ref_table'::regclass; count --------------------------------------------------------------------- 3 (1 row) DROP TABLE dist_table_test_3, rebalance_test_table, ref_table; SELECT 1 FROM master_remove_node('localhost', :master_port); ?column? --------------------------------------------------------------------- 1 (1 row) -- reference table 2 will not have a replica identity, causing the rebalancer to not work -- when ran in the default mode. Instead we need to change the shard transfer mode to make -- it work. This verifies the shard transfer mode used in the rebalancer is used for the -- ensurance of reference table existence. CREATE TABLE t1 (a int PRIMARY KEY, b int); CREATE TABLE r1 (a int PRIMARY KEY, b int); CREATE TABLE r2 (a int, b int); -- we remove worker 2 before creating the tables, this will allow us to have an active -- node without the reference tables SELECT 1 from master_remove_node('localhost', :worker_2_port); ?column? --------------------------------------------------------------------- 1 (1 row) SELECT create_distributed_table('t1','a'); create_distributed_table --------------------------------------------------------------------- (1 row) SELECT create_reference_table('r1'); create_reference_table --------------------------------------------------------------------- (1 row) SELECT create_reference_table('r2'); create_reference_table --------------------------------------------------------------------- (1 row) -- add data so to actually copy data when forcing logical replication for reference tables INSERT INTO r1 VALUES (1,2), (3,4); INSERT INTO r2 VALUES (1,2), (3,4); SELECT 1 from master_add_node('localhost', :worker_2_port); ?column? --------------------------------------------------------------------- 1 (1 row) SELECT rebalance_table_shards(); rebalance_table_shards --------------------------------------------------------------------- (1 row) DROP TABLE t1, r1, r2; -- verify there are no distributed tables before we perform the following tests. Preceding -- test suites should clean up their distributed tables. SELECT count(*) FROM pg_dist_partition; count --------------------------------------------------------------------- 0 (1 row) -- verify a system having only reference tables will copy the reference tables when -- executing the rebalancer SELECT 1 from master_remove_node('localhost', :worker_2_port); ?column? --------------------------------------------------------------------- 1 (1 row) CREATE TABLE r1 (a int PRIMARY KEY, b int); SELECT create_reference_table('r1'); create_reference_table --------------------------------------------------------------------- (1 row) SELECT 1 from master_add_node('localhost', :worker_2_port); ?column? --------------------------------------------------------------------- 1 (1 row) -- count the number of placements for the reference table to verify it is not available on -- all nodes SELECT count(*) FROM pg_dist_shard JOIN pg_dist_shard_placement USING (shardid) WHERE logicalrelid = 'r1'::regclass; count --------------------------------------------------------------------- 1 (1 row) -- rebalance with _only_ a reference table, this should trigger the copy SELECT rebalance_table_shards(); rebalance_table_shards --------------------------------------------------------------------- (1 row) -- verify the reference table is on all nodes after the rebalance SELECT count(*) FROM pg_dist_shard JOIN pg_dist_shard_placement USING (shardid) WHERE logicalrelid = 'r1'::regclass; count --------------------------------------------------------------------- 2 (1 row) -- cleanup tables DROP TABLE r1; -- lastly we need to verify that reference tables are copied before the replication factor -- of other tables is increased. Without the copy of reference tables the replication might -- fail. SELECT 1 from master_remove_node('localhost', :worker_2_port); ?column? --------------------------------------------------------------------- 1 (1 row) CREATE TABLE t1 (a int PRIMARY KEY, b int); CREATE TABLE r1 (a int PRIMARY KEY, b int); SELECT create_distributed_table('t1', 'a'); create_distributed_table --------------------------------------------------------------------- (1 row) SELECT create_reference_table('r1'); create_reference_table --------------------------------------------------------------------- (1 row) SELECT 1 from master_add_node('localhost', :worker_2_port); ?column? --------------------------------------------------------------------- 1 (1 row) -- count the number of placements for the reference table to verify it is not available on -- all nodes SELECT count(*) FROM pg_dist_shard JOIN pg_dist_shard_placement USING (shardid) WHERE logicalrelid = 'r1'::regclass; count --------------------------------------------------------------------- 1 (1 row) SELECT replicate_table_shards('t1', shard_replication_factor := 2); replicate_table_shards --------------------------------------------------------------------- (1 row) -- verify the reference table is on all nodes after replicate_table_shards SELECT count(*) FROM pg_dist_shard JOIN pg_dist_shard_placement USING (shardid) WHERE logicalrelid = 'r1'::regclass; count --------------------------------------------------------------------- 2 (1 row) DROP TABLE t1, r1;