Details
Major Description
Error
ranger-log：
2022-03-21 20:14:29,685 [http-bio-6080-exec-13] ERROR org.apache.ranger.rest.ServiceREST (ServiceREST.java:1709) - createPolicy(RangerPolicy={id={null} guid={null} isEnabled={true} createdBy={null} updatedBy={null} createTime={null} updateTime={null} version={1} service={default-Hive} name={dcp-desensitize_a162c40cdc0140b1848b98415575be6c-1647864869626} policyType={0} policyPriority={0} description={} resourceSignature={4f15e3de95c81650ad869cb93a8c47a132bbec54bdf5de8c01f5075c19754cd7} isAuditEnabled={true} serviceType={null} resources={database={RangerPolicyResource={values={dcp } isExcludes={false} isRecursive={false} }} column={RangerPolicyResource={values={* } isExcludes={false} isRecursive={false} }} table={RangerPolicyResource={values={desensitize_a162c40cdc0140b1848b98415575be6c } isExcludes={false} isRecursive={false} }} } policyLabels={Consoler } policyConditions={} policyItems={RangerPolicyItem={accessTypes={RangerPolicyItemAccess={type={all} isAllowed={true} }} users={tangbiao2 } groups={} roles={} conditions={} delegateAdmin={false} }} denyPolicyItems={} allowExceptions={} denyExceptions={} dataMaskPolicyItems={} rowFilterPolicyItems={} options={} validitySchedules={, zoneName=null, isDenyAllElse={false} }}) failed
javax.persistence.PersistenceException: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: com.mysql.cj.jdbc.exceptions.MySQLTransactionRollbackException: Deadlock found when trying to get lock; try restarting transaction
Error Code: 1213
Call: INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (?, ?, ?, ?, ?, ?, ?)
bind => [7 parameters bound]
Query: ValueReadQuery(name="x_policy_ref_resource_SEQ" sql="SELECT LAST_INSERT_ID()")
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.flush(EntityManagerImpl.java:868)
at sun.reflect.GeneratedMethodAccessor98.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:301)
at com.sun.proxy.$Proxy30.flush(Unknown Source)
at org.apache.ranger.common.db.BaseDao.batchCreate(BaseDao.java:102)
...
mysql-deadlock：
------------------------ LATEST DETECTED DEADLOCK ------------------------ 2022-03-21 09:47:22 0x7ff3a4859700 *** (1) TRANSACTION: TRANSACTION 7036760, ACTIVE 0 sec inserting mysql tables in use 1, locked 1 LOCK WAIT 23 lock struct(s), heap size 1136, 12 row lock(s), undo log entries 2 MySQL thread id 27293, OS thread handle 140684415063808, query id 383930 192.168.0.76 DHCloudBG update INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 12:47:22.666', 13921, 5, 'database', '2022-03-20 12:47:22.681', 1) *** (1) WAITING FOR THIS LOCK TO BE GRANTED: RECORD LOCKS space id 531 page no 4 n bits 376 index x_policy_ref_res_UK_polId_resDefId of table `ranger`.`x_policy_ref_resource` trx id 7036760 lock_mode X insert intention waiting Record lock, heap no 1 PHYSICAL RECORD: n_fields 1; compact format; info bits 0 0: len 8; hex 73757072656d756d; asc supremum;; *** (2) TRANSACTION: TRANSACTION 7036759, ACTIVE 0 sec inserting mysql tables in use 1, locked 1 23 lock struct(s), heap size 1136, 12 row lock(s), undo log entries 2 MySQL thread id 27295, OS thread handle 140684413998848, query id 383932 192.168.0.76 DHCloudBG update INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 12:47:22.666', 13920, 5, 'database', '2022-03-20 12:47:22.682', 1) *** (2) HOLDS THE LOCK(S): RECORD LOCKS space id 531 page no 4 n bits 376 index x_policy_ref_res_UK_polId_resDefId of table `ranger`.`x_policy_ref_resource` trx id 7036759 lock_mode X Record lock, heap no 1 PHYSICAL RECORD: n_fields 1; compact format; info bits 0 0: len 8; hex 73757072656d756d; asc supremum;; *** (2) WAITING FOR THIS LOCK TO BE GRANTED: RECORD LOCKS space id 531 page no 4 n bits 376 index x_policy_ref_res_UK_polId_resDefId of table `ranger`.`x_policy_ref_resource` trx id 7036759 lock_mode X insert intention waiting Record lock, heap no 1 PHYSICAL RECORD: n_fields 1; compact format; info bits 0 0: len 8; hex 73757072656d756d; asc supremum;;*** WE ROLL BACK TRANSACTION (2)
Description
In our production environment, we may create ranger hive policy in parallel. In this case it will occasionally report deadlock errors. I turned on the general_log in mysql, and captured the sql when the deadlock exception occurred, as shown below (some sql was simplified, and only the sql that caused the deadlock was kept):
2022-03-21T20:16:26.776033+08:00 239903 Query DELETE FROM x_policy_ref_resource WHERE (policy_id = 16032) 2022-03-21T20:16:26.776463+08:00 239902 Query DELETE FROM x_policy_ref_resource WHERE (policy_id = 16033) 2022-03-21T20:16:26.784333+08:00 239903 Query INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 23:16:26.766', 16032, 5, 'database', '2022-03-20 23:16:26.783', 1) 2022-03-21T20:16:26.785484+08:00 239902 Query INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 23:16:26.767', 16033, 5, 'database', '2022-03-20 23:16:26.784', 1) 2022-03-21T20:16:26.787844+08:00 239903 Query INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 23:16:26.766', 16032, 8, 'column', '2022-03-20 23:16:26.786', 1) 2022-03-21T20:16:26.788728+08:00 239903 Query INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 23:16:26.766', 16032, 6, 'table', '2022-03-20 23:16:26.787', 1) 2022-03-21T20:16:26.810405+08:00 239902 Query rollback 2022-03-21T20:16:26.810781+08:00 239902 Query SET autocommit=1 2022-03-21T20:16:26.831309+08:00 239903 Query commit
I exported the data in the x_policy_ref_resource table using mysqldump and simulated it in the local environment and found that there is a deadlock when the sql of the two transactions is executed as following order：
| transation1 | transation2 |
|---|---|
| begin | begin |
| DELETE FROM x_policy_ref_resource WHERE (policy_id = 16032); | |
| DELETE FROM x_policy_ref_resource WHERE (policy_id = 16033); | |
| INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 23:16:26.766', 16032, 5, 'database', '2022-03-20 23:16:26.783', 1); | |
| INSERT INTO x_policy_ref_resource (ADDED_BY_ID, CREATE_TIME, policy_id, resource_def_id, resource_name, UPDATE_TIME, UPD_BY_ID) VALUES (1, '2022-03-20 23:16:26.767', 16033, 5, 'database', '2022-03-20 23:16:26.784', 1); |
- When transaction1 and transaction2 execute delete sql, they will both obtain gap lock, because gap locks are compatible.
- Then transaction 1 executes insert sql, it will try to acquire the insert intention lock, which conflicts with the gap lock held by transaction 2, and enters the lock waiting state.
- Finally, transaction2 executes insert sql, and also tries to acquire the insert intention lock, which conflicts with the gap lock held by transaction1. At this point, it is caught in a cycle where transaction1 waits for transaction 2 to release the gap lock, and transaction2 waits for transaction1 to release the gap lock. Two transactions waiting for each other to release locks eventually lead to a deadlock.