Uploaded image for project: 'MariaDB Server'
  1. MariaDB Server
  2. MDEV-16204

Data inconsistency is observed on the cluster after waiting for table metadata lock occurred on Galera Node

    XMLWordPrintable

Details

    • Bug
    • Status: Closed (View Workflow)
    • Major
    • Resolution: Won't Fix
    • 10.3.6
    • N/A
    • Galera
    • None
    • Galera Master-Master 2 Nodes ;CentOS 7.4.

    Description

      Data inconsistency is observed on the cluster after waiting for table metadata lock occurred on Galera Node

      the wsrep status does not show any indication about the occurred inconsistency ,
      cluster state is given operational and Synced;

      On Node 1 occurred waiting for table metadata lock
      After that next received DDL operations on Node1 stuck .
      On Node 2 however are observed completed operations , Node1 and Node2
      return different results .

      Below on Node1 table CUSTOMER returns results while on Node2
      table CUSTOMER does not exists.

      Node2

       
      MariaDB [(none)]>  select count(*) from tpcc.CUSTOMER ;
      ERROR 1146 (42S02): Table 'tpcc.CUSTOMER' doesn't exist
      
      

      Node1

      MariaDB [(none)]> select count(*) from tpcc.CUSTOMER ;
      +----------+
      | count(*) |
      +----------+
      |    30000 |
      +----------+
      1 row in set (0.030 sec)
       
      
      

      MariaDB [(none)]> show processlist ;
      +----+-------------+-----------------+------+------------+-------+-------------------------------------------+-------------------------------------------+----------+
      | Id | User        | Host            | db   | Command    | Time  | State                                     | Info                                      | Progress |
      +----+-------------+-----------------+------+------------+-------+-------------------------------------------+-------------------------------------------+----------+
      |  1 | system user |                 | NULL | Sleep      | 70918 | Committed 26860                           | NULL                                      |    0.000 |
      |  2 | system user |                 | NULL | Sleep      | 86903 | WSREP aborter idle                        | NULL                                      |    0.000 |
      |  3 | system user |                 | NULL | Daemon     |  NULL | InnoDB purge worker                       | NULL                                      |    0.000 |
      |  4 | system user |                 | NULL | Daemon     |  NULL | InnoDB purge worker                       | NULL                                      |    0.000 |
      |  5 | system user |                 | NULL | Daemon     |  NULL | InnoDB purge coordinator                  | NULL                                      |    0.000 |
      |  6 | system user |                 | NULL | Daemon     |  NULL | InnoDB purge worker                       | NULL                                      |    0.000 |
      |  7 | system user |                 | NULL | Daemon     |  NULL | InnoDB shutdown handler                   | NULL                                      |    0.000 |
      | 13 | root        | localhost       | cctt | Killed     | 62724 | Init                                      | CREATE OR REPLACE TABLE t1 AS SELECT f1() |    0.000 |
      | 14 | root        | localhost       | cctt | Field List |  5423 | Waiting for table metadata lock           |                                           |    0.000 |
      | 25 | root        | localhost       | NULL | Query      |   690 | Waiting for stored function metadata lock | drop function cctt.f1                     |    0.000 |
      | 27 | root        | localhost:40292 | tpcc | Query      |   209 | Checking permissions                      | DROP TABLE IF EXISTS CUSTOMER             |    0.000 |
      | 28 | root        | localhost       | NULL | Query      |     0 | Init                                      | show processlist                          |    0.000 |
      +----+-------------+-----------------+------+------------+-------+-------------------------------------------+-------------------------------------------+----------+
      12 rows in set (0.000 sec)
       
      
      

      \

      MariaDB [(none)]> show status like '%wsrep%' ;
      +------------------------------+-------------------------------------------+
      | Variable_name                | Value                                     |
      +------------------------------+-------------------------------------------+
      | wsrep_apply_oooe             | 0.016129                                  |
      | wsrep_apply_oool             | 0.000000                                  |
      | wsrep_apply_window           | 1.024194                                  |
      | wsrep_causal_reads           | 0                                         |
      | wsrep_cert_deps_distance     | 1.661290                                  |
      | wsrep_cert_index_size        | 34                                        |
      | wsrep_cert_interval          | 0.024194                                  |
      | wsrep_cluster_conf_id        | 88                                        |
      | wsrep_cluster_size           | 2                                         |
      | wsrep_cluster_state_uuid     | 3c15149f-5766-11e8-9a99-22bc53d40581      |
      | wsrep_cluster_status         | Primary                                   |
      | wsrep_commit_oooe            | 0.000000                                  |
      | wsrep_commit_oool            | 0.000000                                  |
      | wsrep_commit_window          | 1.000000                                  |
      | wsrep_connected              | ON                                        |
      | wsrep_desync_count           | 0                                         |
      | wsrep_evs_delayed            |                                           |
      | wsrep_evs_evict_list         |                                           |
      | wsrep_evs_repl_latency       | 0/0/0/0/0                                 |
      | wsrep_evs_state              | OPERATIONAL                               |
      | wsrep_flow_control_paused    | 0.000000                                  |
      | wsrep_flow_control_paused_ns | 0                                         |
      | wsrep_flow_control_recv      | 0                                         |
      | wsrep_flow_control_sent      | 0                                         |
      | wsrep_gcomm_uuid             | d09be1b9-58f0-11e8-a6c7-de268e185d14      |
      | wsrep_incoming_addresses     | 192.168.104.195:3306,192.168.104.196:3306 |
      | wsrep_last_committed         | 26892                                     |
      | wsrep_local_bf_aborts        | 0                                         |
      | wsrep_local_cached_downto    | 26772                                     |
      | wsrep_local_cert_failures    | 0                                         |
      | wsrep_local_commits          | 55                                        |
      | wsrep_local_index            | 1                                         |
      | wsrep_local_recv_queue       | 0                                         |
      | wsrep_local_recv_queue_avg   | 0.004484                                  |
      | wsrep_local_recv_queue_max   | 2                                         |
      | wsrep_local_recv_queue_min   | 0                                         |
      | wsrep_local_replays          | 0                                         |
      | wsrep_local_send_queue       | 0                                         |
      | wsrep_local_send_queue_avg   | 0.000000                                  |
      | wsrep_local_send_queue_max   | 1                                         |
      | wsrep_local_send_queue_min   | 0                                         |
      | wsrep_local_state            | 4                                         |
      | wsrep_local_state_comment    | Synced                                    |
      | wsrep_local_state_uuid       | 3c15149f-5766-11e8-9a99-22bc53d40581      |
      | wsrep_protocol_version       | 7                                         |
      | wsrep_provider_name          | Galera                                    |
      | wsrep_provider_vendor        | Codership Oy <info@codership.com>         |
      | wsrep_provider_version       | 25.3.23(r3789)                            |
      | wsrep_ready                  | ON                                        |
      | wsrep_received               | 223                                       |
      | wsrep_received_bytes         | 20873                                     |
      | wsrep_repl_data_bytes        | 36695                                     |
      | wsrep_repl_keys              | 280                                       |
      | wsrep_repl_keys_bytes        | 4633                                      |
      | wsrep_repl_other_bytes       | 0                                         |
      | wsrep_replicated             | 119                                       |
      | wsrep_replicated_bytes       | 48944                                     |
      | wsrep_thread_count           | 2                                         |
      +------------------------------+-------------------------------------------+
      
      

      It appears consecutively that Node1 hangs on 'drop' and 'create' statements
      at 'Checking permissions' state while Node2 is processing all statements .

      Node 1
      MariaDB [(none)]> create database eee
          -> ;
      use eee;
      Command hangs
      

      Node 1 processlist
      28      root    localhost       NULL    Query   21258   Checking permissions    create database eee    
      

      Node 1
      MariaDB [(none)]> show databases like '%eee%' ;
      Empty set (0.001 sec)
       
       
       
      Node 2
      MariaDB [(none)]>  show databases like '%eee%' ;
      +------------------+
      | Database (%eee%) |
      +------------------+
      | eee              |
      +------------------+
      1 row in set (0.000 sec)
       
      MariaDB [(none)]>
      
      

      Attachments

        Issue Links

          Activity

            People

              seppo Seppo Jaakola
              winstone Zdravelina Sokolovska (Inactive)
              Votes:
              1 Vote for this issue
              Watchers:
              4 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved:

                Git Integration

                  Error rendering 'com.xiplink.jira.git.jira_git_plugin:git-issue-webpanel'. Please contact your Jira administrators.