Test retries

tests/queries/0_stateless/02975_system_zookeeper_retries.reference

@@ -0,0 +1,3 @@
+/keeper	api_version
+/keeper	feature_flags
+1

tests/queries/0_stateless/02975_system_zookeeper_retries.sql

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+-- Tags: zookeeper, no-parallel, no-fasttest
+
+SELECT path, name
+FROM system.zookeeper
+WHERE path = '/keeper'
+ORDER BY path, name
+SETTINGS
+  insert_keeper_retry_initial_backoff_ms = 1,
+  insert_keeper_retry_max_backoff_ms = 20,
+  insert_keeper_fault_injection_probability=0.5,
+  log_comment='02975_system_zookeeper_retries';
+
+
+SYSTEM FLUSH LOGS;
+
+-- Check that there where zk session failures
+SELECT ProfileEvents['ZooKeeperHardwareExceptions'] > 0
+FROM system.query_log
+WHERE current_database = currentDatabase() AND type = 'QueryFinish' AND log_comment='02975_system_zookeeper_retries'
+ORDER BY event_time_microseconds DESC
+LIMIT 1;