21.5.14.9 ndbinfo config_valuestable

在 NDB 7.5.0 中实现的config_valuestable 提供有关节点配置参数值的当前状态的信息。table 中的每一行对应于给定节点上参数的当前值。

• node_id

集群中节点的 ID

• config_param

参数的内部 ID 号

• config_value

参数的当前值

Notes

该 table 的config_param列和config_paramstable 的param_number列使用相同的参数标识符。通过将这些列上的两个 table 连接起来，可以获得有关所需节点配置参数的详细信息。此处显示的查询提供了集群中每个数据节点上所有参数的当前值，按节点 ID 和参数名称排序：

SELECT    v.node_id AS 'Node Id',
          p.param_name AS 'Parameter',
          v.config_value AS 'Value'
FROM      config_values v
JOIN      config_params p
ON        v.config_param=p.param_number
WHERE     p.param_name NOT LIKE '\_\_%'
ORDER BY  v.node_id, p.param_name;

在用于简单测试的小型示例集群上运行时，上一个查询的部分输出：

+---------+------------------------------------------+----------------+
| Node Id | Parameter                                | Value          |
+---------+------------------------------------------+----------------+
|       2 | Arbitration                              | 1              |
|       2 | ArbitrationTimeout                       | 7500           |
|       2 | BackupDataBufferSize                     | 16777216       |
|       2 | BackupDataDir                            | /home/jon/data |
|       2 | BackupDiskWriteSpeedPct                  | 50             |
|       2 | BackupLogBufferSize                      | 16777216       |

...

|       3 | TotalSendBufferMemory                    | 0              |
|       3 | TransactionBufferMemory                  | 1048576        |
|       3 | TransactionDeadlockDetectionTimeout      | 1200           |
|       3 | TransactionInactiveTimeout               | 4294967039     |
|       3 | TwoPassInitialNodeRestartCopy            | 0              |
|       3 | UndoDataBuffer                           | 16777216       |
|       3 | UndoIndexBuffer                          | 2097152        |
+---------+------------------------------------------+----------------+
248 rows in set (0.02 sec)

WHERE子句过滤掉名称以双下划线(__)开头的参数；这些参数保留给 NDB 开发人员用于测试和其他内部使用，不适用于生产 NDB 群集。

您可以通过发出适当的查询来获得更具体，更详细的输出，或两者兼而有之。本示例提供了有关当前为集群中所有数据节点设置的NodeId，NoOfReplicas，HostName，DataMemory，IndexMemory和TotalSendBufferMemory参数的所有类型的可用信息：

SELECT  p.param_name AS Name,
        v.node_id AS Node,
        p.param_type AS Type,
        p.param_default AS 'Default',
        p.param_min AS Minimum,
        p.param_max AS Maximum,
        CASE p.param_mandatory WHEN 1 THEN 'Y' ELSE 'N' END AS 'Required',
        v.config_value AS Current
FROM    config_params p
JOIN    config_values v
ON      p.param_number = v.config_param
WHERE   p. param_name
  IN ('NodeId', 'NoOfReplicas', 'HostName',
      'DataMemory', 'IndexMemory', 'TotalSendBufferMemory')\G

在具有两个用于简单测试的数据节点的小型 NDB 群集上运行时，此查询的输出如下所示：

*************************** 1. row ***************************
    Name: NodeId
    Node: 2
    Type: unsigned
 Default:
 Minimum: 1
 Maximum: 48
Required: Y
 Current: 2
*************************** 2. row ***************************
    Name: HostName
    Node: 2
    Type: string
 Default: localhost
 Minimum:
 Maximum:
Required: N
 Current: 127.0.0.1
*************************** 3. row ***************************
    Name: TotalSendBufferMemory
    Node: 2
    Type: unsigned
 Default: 0
 Minimum: 262144
 Maximum: 4294967039
Required: N
 Current: 0
*************************** 4. row ***************************
    Name: NoOfReplicas
    Node: 2
    Type: unsigned
 Default: 2
 Minimum: 1
 Maximum: 4
Required: N
 Current: 2
*************************** 5. row ***************************
    Name: DataMemory
    Node: 2
    Type: unsigned
 Default: 102760448
 Minimum: 1048576
 Maximum: 1099511627776
Required: N
 Current: 524288000
*************************** 6. row ***************************
    Name: NodeId
    Node: 3
    Type: unsigned
 Default:
 Minimum: 1
 Maximum: 48
Required: Y
 Current: 3
*************************** 7. row ***************************
    Name: HostName
    Node: 3
    Type: string
 Default: localhost
 Minimum:
 Maximum:
Required: N
 Current: 127.0.0.1
*************************** 8. row ***************************
    Name: TotalSendBufferMemory
    Node: 3
    Type: unsigned
 Default: 0
 Minimum: 262144
 Maximum: 4294967039
Required: N
 Current: 0
*************************** 9. row ***************************
    Name: NoOfReplicas
    Node: 3
    Type: unsigned
 Default: 2
 Minimum: 1
 Maximum: 4
Required: N
 Current: 2
*************************** 10. row ***************************
    Name: DataMemory
    Node: 3
    Type: unsigned
 Default: 102760448
 Minimum: 1048576
 Maximum: 1099511627776
Required: N
 Current: 524288000
10 rows in set (0.01 sec)