OceanBase常用命令

OceanBase常用命令

整理一些OB中常用的查询语句,解决一些OB常用的运维操作,后期不断补充吧。

租户类

  • • OB支持多租户,默认是sys租户,通常我们都需要自己创建一个租户供业务使用,创建一个完成租户顺序是 unit->resource pool->tenant ,当然在最开始创建租户时,可能会遇到报错就是资源不足的问题,所以首先要确认下资源可用情况:


SELECT a.zone,concat(a.svr_ip,':',a.svr_port) observer, cpu_total, cpu_assigned, (cpu_total-cpu_assigned) cpu_free,
                                                                                                          mem_total/1024/1024/1024 mem_total_gb,
                                                                                                          mem_assigned/1024/1024/1024 mem_assign_gb,
                                                                                                          (mem_total-mem_assigned)/1024/1024/1024 mem_free_gb
FROM __all_virtual_server_stat a
JOIN __all_server b ON (a.svr_ip=b.svr_ip
                        AND a.svr_port=b.svr_port)
ORDER BY a.zone,
         a.svr_ip ;
         

// 4.0之后:
SELECT SVR_IP ,
        SVR_PORT ,
        ZONE ,
        SQL_PORT ,
        CPU_CAPACITY ,
        CPU_CAPACITY_MAX ,
        CPU_ASSIGNED ,
        CPU_ASSIGNED_MAX ,
        MEM_CAPACITY/1024/1024/1024 as  MEM_CAPACITY_GB ,
        MEM_ASSIGNED/1024/1024/1024 as MEM_ASSIGNED_GB,
        LOG_DISK_CAPACITY/1024/1024/1024 as LOG_DISK_CAPACITY_GB  ,
        LOG_DISK_ASSIGNED/1024/1024/1024 as LOG_DISK_ASSIGNED_GB ,
        LOG_DISK_IN_USE/1024/1024/1024 as LOG_DISK_IN_USE_GB ,
        DATA_DISK_CAPACITY/1024/1024/1024 as DATA_DISK_CAPACITY_GB ,
        DATA_DISK_IN_USE/1024/1024/1024 as DATA_DISK_IN_USE_GB,
        DATA_DISK_HEALTH_STATUS ,
        MEMORY_LIMIT/1024/1024/1024 as MEMORY_LIMIT_GB 
FROM GV$OB_SERVERS;

//结果如下面看到 cpu、mem、disk 可使用最大资源和已使用情况,后面创建租户时就知道最大能使用的资源了。:
+---------------+----------+-------+----------+--------------+------------------+--------------+------------------+-----------------+-----------------+----------------------+----------------------+--------------------+-----------------------+---------------------+-------------------------+-----------------+
| SVR_IP        | SVR_PORT | ZONE  | SQL_PORT | CPU_CAPACITY | CPU_CAPACITY_MAX | CPU_ASSIGNED | CPU_ASSIGNED_MAX | MEM_CAPACITY_GB | MEM_ASSIGNED_GB | LOG_DISK_CAPACITY_GB | LOG_DISK_ASSIGNED_GB | LOG_DISK_IN_USE_GB | DATA_DISK_CAPACITY_GB | DATA_DISK_IN_USE_GB | DATA_DISK_HEALTH_STATUS | MEMORY_LIMIT_GB |
+---------------+----------+-------+----------+--------------+------------------+--------------+------------------+-----------------+-----------------+----------------------+----------------------+--------------------+-----------------------+---------------------+-------------------------+-----------------+
| 10.140.118.7  |     2882 | zone3 |     2881 |           16 |               16 |            1 |                1 |  8.000000000000 |  2.000000000000 |      30.000000000000 |       2.000000000000 |     1.625000000000 |       60.000000000000 |      1.257812500000 | NORMAL                  | 10.000000000000 |
| 10.140.114.12 |     2882 | zone1 |     2881 |           16 |               16 |            1 |                1 |  8.000000000000 |  2.000000000000 |      30.000000000000 |       2.000000000000 |     1.625000000000 |       19.990234375000 |      1.271484375000 | NORMAL                  | 10.000000000000 |
| 10.140.60.14  |     2882 | zone2 |     2881 |           16 |               16 |            1 |                1 |  8.000000000000 |  2.000000000000 |      30.000000000000 |       2.000000000000 |     1.625000000000 |       60.000000000000 |      1.257812500000 | NORMAL                  | 10.000000000000 |
+---------------+----------+-------+----------+--------------+------------------+--------------+------------------+-----------------+-----------------+----------------------+----------------------+--------------------+-----------------------+---------------------+-------------------------+-----------------+
3 rows in set (0.005 sec)
  • • 创建Unit

// 创建Unit
MySQL [oceanbase]> create resource unit S2 max_cpu=2, min_cpu=2, max_memory='4G', min_memory='2G', max_iops=10000, min_iops=1000, max_session_num=1000000, max_disk_size='50G';
Query OK, 0 rows affected (0.009 sec)

//4.0之后:
obclient [oceanbase]> create resource unit S2 max_cpu=7, min_cpu=2, MEMORY_SIZE='8G', max_iops=10000, min_iops=10000;
Query OK, 0 rows affected (0.011 sec)

// 目前对IOPS的限制是不生效的
  • • 创建资源池

//创建资源池,unit_num根据自身实际情况修改,unit_num不超过zone内机器数量即可
MySQL [oceanbase]>  create resource pool pool_2 unit='S2', unit_num=1;
Query OK, 0 rows affected (0.021 sec)

在这里会经常遇到报错,说资源不足,也可以单独查看unit资源配置情况:

obclient [oceanbase]> create resource unit S2 max_cpu=7, min_cpu=2, MEMORY_SIZE='10G', max_iops=10000, min_iops=10000;
Query OK, 0 rows affected (0.010 sec)

obclient [oceanbase]>
obclient [oceanbase]>  create resource pool pool_2 unit='S2', unit_num=1;
ERROR 4733 (HY000): zone 'zone1' resource not enough to hold 1 unit. You can check resource info by views: DBA_OB_UNITS, GV$OB_UNITS, GV$OB_SERVERS.
server '"10.140.114.12:2882"' MEMORY resource not enough


SELECT gmt_create,
       gmt_modified,
       unit_config_id,
       name,
       max_cpu,
       min_cpu,
       memory_size/1024/1024/1024 AS memory_size_gb,
       log_disk_size/1024/1024/1024 AS log_disk_size_gb ,
       max_iops,
       min_iops,
       iops_weight
FROM __all_unit_config ;

+----------------------------+----------------------------+----------------+-----------------+---------+---------+-----------------+------------------+----------+----------+-------------+
| gmt_create                 | gmt_modified               | unit_config_id | name            | max_cpu | min_cpu | memory_size_gb  | log_disk_size_gb | max_iops | min_iops | iops_weight |
+----------------------------+----------------------------+----------------+-----------------+---------+---------+-----------------+------------------+----------+----------+-------------+
| 2023-02-19 10:23:07.392620 | 2023-02-19 10:23:07.392620 |              1 | sys_unit_config |       1 |       1 |  2.000000000000 |   2.000000000000 |    10000 |    10000 |           1 |
| 2023-02-23 11:09:04.767938 | 2023-02-23 11:09:04.767938 |           1002 | S2              |       7 |       2 | 10.000000000000 |  30.000000000000 |    10000 |    10000 |           0 |
+----------------------------+----------------------------+----------------+-----------------+---------+---------+-----------------+------------------+----------+----------+-------------+

向上面这种情况,看到Unit的memory_size超过了MEM_CAPACITY-MEM_ASSIGNED可用的内存大小,这块有两种方法调整内存大小:

  1. 1. 删除Unit重新创建,降低内存大小

  2. 2. 使用命令调整Unit内存大小,但需要注意log_disk_size默认是Unit创建时内存大小的三倍,调整内存后log_disk_size并不会自动变化,可根据情况同样用命令调整 修改unit资源限制:

ALTER RESOURCE unit S2 MEMORY_SIZE='6G';
ALTER RESOURCE unit S2 log_disk_size='18G';
  • • 创建租户

MySQL [oceanbase]> CREATE TENANT IF NOT EXISTS tenant_2
    ->     charset='utf8mb4',
    ->     replica_num=3,
    ->     zone_list=('zone1','zone2','zone3'),
    ->     primary_zone='RANDOM',
    ->     resource_pool_list=('pool_2');
Query OK, 0 rows affected (1.477 sec)
  • • 以Pool维度查看资源使用情况:

SELECT t1.name resource_pool_name,
       t2.`name` unit_config_name,
       t2.max_cpu,
       t2.min_cpu,
       t2.max_memory/1024/1024/1024 max_mem_gb,
                                     t2.min_memory/1024/1024/1024 min_mem_gb,
                                     t3.unit_id,
                                     t3.zone,
                                     concat(t3.svr_ip,':',t3.`svr_port`) observer,
                                     t4.tenant_id,
                                     t4.tenant_name
FROM __all_resource_pool t1
JOIN __all_unit_config t2 ON (t1.unit_config_id=t2.unit_config_id)
JOIN __all_unit t3 ON (t1.`resource_pool_id` = t3.`resource_pool_id`)
LEFT JOIN __all_tenant t4 ON (t1.tenant_id=t4.tenant_id)
ORDER BY t1.`resource_pool_id`,
         t2.`unit_config_id`,
         t3.unit_id ;
         
         
// 4.0之后
SELECT t1.name resource_pool_name,
       t2.`name` unit_config_name,
       t2.max_cpu,
       t2.min_cpu,
       t2.memory_size/1024/1024/1024 memory_size,
                                     t3.unit_id,
                                     t3.zone,
                                     concat(t3.svr_ip,':',t3.`svr_port`) observer,
                                     t4.tenant_id,
                                     t4.tenant_name
FROM __all_resource_pool t1
JOIN __all_unit_config t2 ON (t1.unit_config_id=t2.unit_config_id)
JOIN __all_unit t3 ON (t1.`resource_pool_id` = t3.`resource_pool_id`)
LEFT JOIN __all_tenant t4 ON (t1.tenant_id=t4.tenant_id)
ORDER BY t1.`resource_pool_id`,
         t2.`unit_config_id`,
         t3.unit_id ;
  • • 以zone维度查看资源使用情况(适用于3.x版本):

SELECT a.zone,concat(a.svr_ip,':',a.svr_port) observer, cpu_total, cpu_assigned, (cpu_total-cpu_assigned) cpu_free,
                                                                                                          mem_total/1024/1024/1024 mem_total_gb,
                                                                                                          mem_assigned/1024/1024/1024 mem_assign_gb,
                                                                                                          (mem_total-mem_assigned)/1024/1024/1024 mem_free_gb
FROM __all_virtual_server_stat a
JOIN __all_server b ON (a.svr_ip=b.svr_ip
                        AND a.svr_port=b.svr_port)
ORDER BY a.zone,
         a.svr_ip ;
  • • 查看租户对应的Unit数量,Zone信息

SELECT pool.tenant_id,
       tenant.tenant_name,
       name AS pool_name,
       unit_config_id,
       unit_count,
       unit.unit_id,
       pool.zone_list,
       unit.svr_ip
FROM __all_resource_pool pool
INNER JOIN __all_tenant tenant ON pool.tenant_id=tenant.tenant_id
INNER JOIN __all_unit unit ON pool.resource_pool_id=unit.resource_pool_id
WHERE pool.tenant_id>=1
ORDER BY tenant.tenant_name,
         zone_list;

转储和合并

  • • 查看租户内存使用情况,当MEMSTORE_USED>FREEZE_TRIGGER时就会触发转储


select /*+ READ_CONSISTENCY(WEAK),query_timeout(100000000) */ TENANT_ID,IP,
round(ACTIVE/1024/1024/1024,2)ACTIVE_GB,
round(TOTAL/1024/1024/1024,2) TOTAL_GB,
round(FREEZE_TRIGGER/1024/1024/1024,2) FREEZE_TRIGGER_GB,
round(TOTAL/FREEZE_TRIGGER*100,2) percent_trigger,
round(MEM_LIMIT/1024/1024/1024,2) MEM_LIMIT_GB
from gv$memstore
where tenant_id >1000 or TENANT_ID=1
order by tenant_id,TOTAL_GB desc;

//4.0之后
select round(ACTIVE_SPAN/1024/1024/1024,2) as ACTIVE_SPAN_GB , round(FREEZE_TRIGGER/1024/1024/1024,2) as FREEZE_TRIGGER_GB, round(MEMSTORE_USED/1024/1024/1024,2) as MEMSTORE_USED_GB , round(MEMSTORE_LIMIT/1024/1024/1024, 2) as MEMSTORE_LIMIT_GB from GV$OB_MEMSTORE where tenant_id =  1002;

+----------------+-------------------+------------------+-------------------+
| ACTIVE_SPAN_GB | FREEZE_TRIGGER_GB | MEMSTORE_USED_GB | MEMSTORE_LIMIT_GB |
+----------------+-------------------+------------------+-------------------+
|           0.04 |              0.30 |             0.04 |              3.00 |
|           0.03 |              0.30 |             0.03 |              3.00 |
|           0.03 |              0.30 |             0.03 |              3.00 |
+----------------+-------------------+------------------+-------------------+
3 rows in set (0.003 sec)
  • • 查看MemStore使用率达到freeze_trigger_percentage而触发的租户级转储

select * from __all_server_event_history where event like '%merge%' or event like '%minor%' order by gmt_create desc limit 10;
  • • 可以单独针对一张表,查看SSTable的情况,先通过oceanbase.CDB_OB_TABLE_LOCATIONS查看表的TABLET_ID:

obclient [oceanbase]> select * from oceanbase.CDB_OB_TABLE_LOCATIONS where tenant_id = 1002 and database_name = 'sysbenchdb';
+-----------+---------------+------------+----------+------------+----------------+-------------------+------------+---------------+-----------+-------+-------+---------------+----------+----------+--------------+
| TENANT_ID | DATABASE_NAME | TABLE_NAME | TABLE_ID | TABLE_TYPE | PARTITION_NAME | SUBPARTITION_NAME | INDEX_NAME | DATA_TABLE_ID | TABLET_ID | LS_ID | ZONE  | SVR_IP        | SVR_PORT | ROLE     | REPLICA_TYPE |
+-----------+---------------+------------+----------+------------+----------------+-------------------+------------+---------------+-----------+-------+-------+---------------+----------+----------+--------------+
|      1002 | sysbenchdb    | sbtest1    |   500015 | USER TABLE | NULL           | NULL              | NULL       |          NULL |    200008 |  1002 | zone1 | 10.140.114.12 |     2882 | FOLLOWER | FULL         |
|      1002 | sysbenchdb    | sbtest1    |   500015 | USER TABLE | NULL           | NULL              | NULL       |          NULL |    200008 |  1002 | zone2 | 10.140.60.14  |     2882 | LEADER   | FULL         |
|      1002 | sysbenchdb    | sbtest1    |   500015 | USER TABLE | NULL           | NULL              | NULL       |          NULL |    200008 |  1002 | zone3 | 10.140.118.7  |     2882 | FOLLOWER | FULL         |
+-----------+---------------+------------+----------+------------+----------------+-------------------+------------+---------------+-----------+-------+-------+---------------+----------+----------+--------------+
3 rows in set (0.023 sec)

当达到minor_compact_trigger设置个数后,会触发MINOR_MERGE或MINOR_MERGE类型的转储

obclient [oceanbase]> SELECT count(*) , type FROM oceanbase.GV$OB_TABLET_COMPACTION_HISTORY where tenant_id = 1002 AND TABLET_ID = 2000068 and svr_ip = '10.140.114.12' group  by  type;
+----------+------------+
| count(*) | type       |
+----------+------------+
|        6 | MINI_MERGE |
+----------+------------+
1 row in set (0.005 sec)

obclient [oceanbase]> SELECT count(*) , type FROM oceanbase.GV$OB_TABLET_COMPACTION_HISTORY where tenant_id = 1002 AND TABLET_ID = 200008 and svr_ip = '10.140.114.12' group  by  type;
+----------+-------------+
| count(*) | type        |
+----------+-------------+
|        7 | MINI_MERGE  |
|        1 | MINOR_MERGE |
+----------+-------------+
2 rows in set (0.004 sec)

手工执行合并:

alter system major freeze;

查看合并进程情况:

select * from oceanbase.__all_zone where name = 'merge_status';

4.0+
SELECT * FROM oceanbase.CDB_OB_ZONE_MAJOR_COMPACTIONG

表相关

OB中有分区表,每个分区表都是三副本放到不同的节点上,有Leader和Follower之分,可以用过下面语句查看分区的分部情况:

SELECT tenant.tenant_name,
       meta.table_id,
       tab.table_name,
       partition_id,
       ZONE,
       concat(svr_ip, ':', svr_port) observer ,
       CASE
           WHEN ROLE=1 THEN 'leader'
           WHEN ROLE=2 THEN 'follower'
           ELSE NULL
       END AS ROLE,
       tab.primary_zone
FROM __all_virtual_meta_table meta
INNER JOIN __all_tenant tenant ON meta.tenant_id=tenant.tenant_id
INNER JOIN __all_virtual_table tab ON meta.tenant_id=tab.tenant_id
AND meta.table_id=tab.table_id
WHERE tenant.tenant_id='1001'
ORDER BY tenant.tenant_name,
         TABLE_NAME,
         partition_id,
         ZONE ;
         
4.0之后  sys租户中查询
select * from oceanbase.CDB_OB_TABLE_LOCATIONS where tenant_id = 1002 and database_name = 'sysbenchdb';

用户租户内查询
obclient [oceanbase]> select * from DBA_OB_TABLE_LOCATIONS  where database_name = 'sysbenchdb';
+---------------+------------+----------+------------+----------------+-------------------+------------+---------------+-----------+-------+-------+---------------+----------+----------+--------------+
| DATABASE_NAME | TABLE_NAME | TABLE_ID | TABLE_TYPE | PARTITION_NAME | SUBPARTITION_NAME | INDEX_NAME | DATA_TABLE_ID | TABLET_ID | LS_ID | ZONE  | SVR_IP        | SVR_PORT | ROLE     | REPLICA_TYPE |
+---------------+------------+----------+------------+----------------+-------------------+------------+---------------+-----------+-------+-------+---------------+----------+----------+--------------+
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p0             | NULL              | NULL       |          NULL |    200017 |  1001 | zone1 | 10.140.114.12 |     2882 | LEADER   | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p0             | NULL              | NULL       |          NULL |    200017 |  1001 | zone2 | 10.140.60.14  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p0             | NULL              | NULL       |          NULL |    200017 |  1001 | zone3 | 10.140.118.7  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p1             | NULL              | NULL       |          NULL |    200018 |  1001 | zone1 | 10.140.114.12 |     2882 | LEADER   | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p1             | NULL              | NULL       |          NULL |    200018 |  1001 | zone2 | 10.140.60.14  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p1             | NULL              | NULL       |          NULL |    200018 |  1001 | zone3 | 10.140.118.7  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p2             | NULL              | NULL       |          NULL |    200019 |  1002 | zone1 | 10.140.114.12 |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p2             | NULL              | NULL       |          NULL |    200019 |  1002 | zone2 | 10.140.60.14  |     2882 | LEADER   | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p2             | NULL              | NULL       |          NULL |    200019 |  1002 | zone3 | 10.140.118.7  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p3             | NULL              | NULL       |          NULL |    200020 |  1002 | zone1 | 10.140.114.12 |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p3             | NULL              | NULL       |          NULL |    200020 |  1002 | zone2 | 10.140.60.14  |     2882 | LEADER   | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p3             | NULL              | NULL       |          NULL |    200020 |  1002 | zone3 | 10.140.118.7  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p4             | NULL              | NULL       |          NULL |    200021 |  1003 | zone1 | 10.140.114.12 |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p4             | NULL              | NULL       |          NULL |    200021 |  1003 | zone2 | 10.140.60.14  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p4             | NULL              | NULL       |          NULL |    200021 |  1003 | zone3 | 10.140.118.7  |     2882 | LEADER   | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p5             | NULL              | NULL       |          NULL |    200022 |  1003 | zone1 | 10.140.114.12 |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p5             | NULL              | NULL       |          NULL |    200022 |  1003 | zone2 | 10.140.60.14  |     2882 | FOLLOWER | FULL         |
| sysbenchdb    | cust_info  |   500020 | USER TABLE | p5             | NULL              | NULL       |          NULL |    200022 |  1003 | zone3 | 10.140.118.7  |     2882 | LEADER   | FULL         |
+---------------+------------+----------+------------+----------------+-------------------+------------+---------------+-----------+-------+-------+---------------+----------+----------+--------------+
18 rows in set (0.008 sec)
  • • 查看表分布情况(tablegroup,适用于3.x版本):

SELECT tenant.tenant_name,
       meta.table_id,
       tab.table_name,
       tg.tablegroup_name,
       partition_id,
       ZONE,
       concat(svr_ip, ':', svr_port) observer ,
       CASE
           WHEN ROLE=1 THEN 'leader'
           WHEN ROLE=2 THEN 'follower'
           ELSE NULL
       END AS ROLE,
       tab.primary_zone
FROM __all_virtual_meta_table meta
INNER JOIN __all_tenant tenant ON meta.tenant_id=tenant.tenant_id
INNER JOIN __all_virtual_table tab ON meta.tenant_id=tab.tenant_id
INNER JOIN __all_tablegroup tg on (tab.tenant_id = tg.tenant_id and tab.tablegroup_id = tg.tablegroup_id)
AND meta.table_id=tab.table_id
WHERE tenant.tenant_id='1'
ORDER BY tenant.tenant_name,
         TABLE_NAME,
         partition_id,
         ZONE ;
  • • 查看sql执行情况(适用于3.x版本):

SELECT /*+ read_consistency(weak) query_timeout(1000000000) */ usec_to_time(request_time) req_time,
                                                               svr_Ip,
                                                               trace_id,
                                                               sid,
                                                               client_ip,
                                                               tenant_id,
                                                               tenant_name,
                                                               user_name,
                                                               db_name,
                                                               query_sql,
                                                               affected_rows,
                                                               ret_code,
                                                               event,
                                                               STATE,
                                                               elapsed_time,
                                                               execute_time,
                                                               queue_time,
                                                               decode_time,
                                                               get_plan_time,
                                                               block_cache_hit,
                                                               bloom_filter_cache_Hit,
                                                               block_index_cache_hit,
                                                               disk_reads,
                                                               retry_cnt,
                                                               table_scan,
                                                               memstore_read_row_count,
                                                               ssstore_read_row_count,
                                                               round(request_memory_used/1024/1024) req_mem_mb
FROM gv$sql_audit
WHERE tenant_id=1
  AND user_name IN ('u_sysbench')
ORDER BY request_time DESC LIMIT 100;


原文始发于微信公众号(懒人的记录):OceanBase常用命令

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