Some debugging of the test

src/test/regress/citus_tests/common.py

@@ -545,6 +545,21 @@ class QueryRunner(ABC):
         with self.cur(**kwargs) as cur:
             cur.execute(query, params=params)
 
+    def sql_row(self, query, params=None, allow_empty_result=False, **kwargs):
+        """Run an SQL query that returns a single row and returns this row
+
+        This opens a new connection and closes it once the query is done
+        """
+        with self.cur(**kwargs) as cur:
+            cur.execute(query, params=params)
+            result = cur.fetchall()
+
+            if allow_empty_result and len(result) == 0:
+                return None
+
+            assert len(result) == 1
+            return result[0]
+
     def sql_value(self, query, params=None, allow_empty_result=False, **kwargs):
         """Run an SQL query that returns a single cell and return this value
 

src/test/regress/citus_tests/test/test_auto_shard_split.py

@@ -1,18 +1,22 @@
 import psycopg
 import pytest
+from pprint import pprint
 
 def test_isolate(cluster):
 
-    cluster.coordinator.restart()
+    cluster.coordinator.configure("citus.split_shard_group_size_threshold to 100")
-    cluster.coordinator.sql("SET citus.split_shard_group_size_threshold to 100")
+    cluster.coordinator.reload()
     cluster.coordinator.sql("CREATE TABLE test_row(i integer)")
     cluster.coordinator.sql("SELECT create_distributed_table('test_row','i',shard_count:=1)")
+    cluster.coordinator.sql("ANALYZE test_row")
     cluster.coordinator.sql("INSERT INTO test_row SELECT 1 from generate_series(1,20000) ")
+    print(cluster.coordinator.sql_row("select count(*), avg(i) from test_row"))
 
     row_count1 = cluster.coordinator.sql_value("SELECT count(*) FROM pg_dist_shard")
 
     query = "SELECT citus_auto_shard_split_start('block_writes')"
     jobId = cluster.coordinator.sql_value(query)
+    print(cluster.coordinator.sql_value("select command from pg_dist_background_task where status = 'runnable'"))
 
     cluster.coordinator.sql("SELECT citus_job_wait({})".format(jobId))
 
@@ -23,8 +27,8 @@ def test_isolate(cluster):
 
 def test_split(cluster):
 
-    cluster.coordinator.restart()
+    cluster.coordinator.configure("citus.split_shard_group_size_threshold to 100")
-    cluster.coordinator.sql("SET citus.split_shard_group_size_threshold to 100")
+    cluster.coordinator.reload()
     cluster.coordinator.sql("CREATE TABLE test_row(i integer)")
     cluster.coordinator.sql("SELECT create_distributed_table('test_row','i',shard_count:=1)")
     cluster.coordinator.sql("INSERT INTO test_row SELECT generate_series(1,20000) ")
@@ -33,9 +37,10 @@ def test_split(cluster):
 
     query = "SELECT citus_auto_shard_split_start('block_writes')"
     jobId = cluster.coordinator.sql_value(query)
+    print(cluster.coordinator.sql_value("select command from pg_dist_background_task where status = 'runnable'"))
 
     cluster.coordinator.sql("SELECT citus_job_wait({})".format(jobId))
 
     row_count2 = cluster.coordinator.sql_value("SELECT count(*) FROM pg_dist_shard")
 
-    assert row_count2==row_count1+1, "Shard didn't get split"
+    assert row_count2==row_count1+1, "Shard didn't get split"