mirror of https://github.com/citusdata/citus.git
172 lines
6.9 KiB
Plaintext
172 lines
6.9 KiB
Plaintext
--
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-- MULTI_TASK_ASSIGNMENT
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--
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ALTER SEQUENCE pg_catalog.pg_dist_shardid_seq RESTART 880000;
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ALTER SEQUENCE pg_catalog.pg_dist_jobid_seq RESTART 880000;
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SET citus.explain_distributed_queries TO off;
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-- Check that our policies for assigning tasks to worker nodes run as expected.
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-- To test this, we first create a shell table, and then manually insert shard
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-- and shard placement data into system catalogs. We next run Explain command,
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-- and check that tasks are assigned to worker nodes as expected.
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CREATE TABLE task_assignment_test_table (test_id integer);
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SELECT master_create_distributed_table('task_assignment_test_table', 'test_id', 'append');
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master_create_distributed_table
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---------------------------------
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(1 row)
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-- Create logical shards with shardids 200, 201, and 202
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INSERT INTO pg_dist_shard (logicalrelid, shardid, shardstorage, shardminvalue, shardmaxvalue)
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SELECT pg_class.oid, series.index, 'r', 1, 1000
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FROM pg_class, generate_series(200, 202) AS series(index)
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WHERE pg_class.relname = 'task_assignment_test_table';
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-- Create shard placements for shard 200 and 201
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INSERT INTO pg_dist_shard_placement (shardid, shardstate, shardlength, nodename, nodeport)
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SELECT 200, 1, 1, nodename, nodeport
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FROM pg_dist_shard_placement
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GROUP BY nodename, nodeport
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ORDER BY nodename, nodeport ASC
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LIMIT 2;
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INSERT INTO pg_dist_shard_placement (shardid, shardstate, shardlength, nodename, nodeport)
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SELECT 201, 1, 1, nodename, nodeport
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FROM pg_dist_shard_placement
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GROUP BY nodename, nodeport
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ORDER BY nodename, nodeport ASC
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LIMIT 2;
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-- Create shard placements for shard 202
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INSERT INTO pg_dist_shard_placement (shardid, shardstate, shardlength, nodename, nodeport)
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SELECT 202, 1, 1, nodename, nodeport
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FROM pg_dist_shard_placement
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GROUP BY nodename, nodeport
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ORDER BY nodename, nodeport DESC
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LIMIT 2;
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-- Start transaction block to avoid auto commits. This avoids additional debug
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-- messages from getting printed at real transaction starts and commits.
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BEGIN;
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-- Increase log level to see which worker nodes tasks are assigned to. Note that
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-- the following log messages print node name and port numbers; and node numbers
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-- in regression tests depend upon PG_VERSION_NUM.
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SET client_min_messages TO DEBUG3;
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DEBUG: CommitTransactionCommand
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-- First test the default greedy task assignment policy
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SET citus.task_assignment_policy TO 'greedy';
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: CommitTransactionCommand
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EXPLAIN SELECT count(*) FROM task_assignment_test_table;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: assigned task 6 to node localhost:57637
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DEBUG: assigned task 2 to node localhost:57638
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DEBUG: assigned task 4 to node localhost:57637
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DEBUG: CommitTransactionCommand
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QUERY PLAN
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------------------------------------------------------------
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explain statements for distributed queries are not enabled
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(1 row)
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EXPLAIN SELECT count(*) FROM task_assignment_test_table;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: assigned task 6 to node localhost:57637
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DEBUG: assigned task 2 to node localhost:57638
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DEBUG: assigned task 4 to node localhost:57637
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DEBUG: CommitTransactionCommand
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QUERY PLAN
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------------------------------------------------------------
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explain statements for distributed queries are not enabled
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(1 row)
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-- Next test the first-replica task assignment policy
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SET citus.task_assignment_policy TO 'first-replica';
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: CommitTransactionCommand
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EXPLAIN SELECT count(*) FROM task_assignment_test_table;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: assigned task 6 to node localhost:57637
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DEBUG: assigned task 4 to node localhost:57637
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DEBUG: assigned task 2 to node localhost:57638
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DEBUG: CommitTransactionCommand
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QUERY PLAN
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------------------------------------------------------------
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explain statements for distributed queries are not enabled
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(1 row)
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EXPLAIN SELECT count(*) FROM task_assignment_test_table;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: assigned task 6 to node localhost:57637
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DEBUG: assigned task 4 to node localhost:57637
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DEBUG: assigned task 2 to node localhost:57638
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DEBUG: CommitTransactionCommand
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QUERY PLAN
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------------------------------------------------------------
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explain statements for distributed queries are not enabled
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(1 row)
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-- Round-robin task assignment relies on the current jobId. We therefore need to
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-- ensure that jobIds start with an odd number here; this way, task assignment
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-- debug messages always produce the same output. Also, we make sure that the
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-- following case statement always prints out "1" as the query's result.
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SELECT case when (currval('pg_dist_jobid_seq') % 2) = 0
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then nextval('pg_dist_jobid_seq') % 2
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else 1 end;
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DEBUG: StartTransactionCommand
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DEBUG: CommitTransactionCommand
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case
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------
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1
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(1 row)
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-- Finally test the round-robin task assignment policy
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SET citus.task_assignment_policy TO 'round-robin';
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: CommitTransactionCommand
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EXPLAIN SELECT count(*) FROM task_assignment_test_table;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: assigned task 6 to node localhost:57637
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DEBUG: assigned task 4 to node localhost:57637
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DEBUG: assigned task 2 to node localhost:57638
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DEBUG: CommitTransactionCommand
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QUERY PLAN
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------------------------------------------------------------
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explain statements for distributed queries are not enabled
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(1 row)
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EXPLAIN SELECT count(*) FROM task_assignment_test_table;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: assigned task 6 to node localhost:57638
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DEBUG: assigned task 4 to node localhost:57638
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DEBUG: assigned task 2 to node localhost:57637
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DEBUG: CommitTransactionCommand
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QUERY PLAN
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------------------------------------------------------------
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explain statements for distributed queries are not enabled
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(1 row)
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EXPLAIN SELECT count(*) FROM task_assignment_test_table;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: assigned task 6 to node localhost:57637
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DEBUG: assigned task 4 to node localhost:57637
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DEBUG: assigned task 2 to node localhost:57638
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DEBUG: CommitTransactionCommand
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QUERY PLAN
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------------------------------------------------------------
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explain statements for distributed queries are not enabled
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(1 row)
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RESET citus.task_assignment_policy;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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DEBUG: CommitTransactionCommand
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RESET client_min_messages;
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DEBUG: StartTransactionCommand
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DEBUG: ProcessUtility
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COMMIT;
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