MySQL 8.4 版本注意事項
config_values
資料表提供關於節點組態參數值的目前狀態資訊。資料表中的每一列對應於指定節點上參數的目前值。
config_values
資料表包含下列欄位
node_id
叢集中節點的 ID
config_param
參數的內部 ID 編號
config_value
參數的目前值
註解
此資料表的 config_param
欄位與 config_params
資料表的 param_number
欄位使用相同的參數識別碼。透過在這些欄位上聯結兩個資料表,您可以取得關於所需節點組態參數的詳細資訊。此處顯示的查詢提供叢集中每個資料節點上所有參數的目前值,並依節點 ID 和參數名稱排序
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;
先前查詢在用於簡單測試的小型範例叢集上執行時的部分輸出
+---------+------------------------------------------+----------------+
| 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
子句會篩選出名稱以雙底線 (__
) 開頭的參數;這些參數保留給 NDB 開發人員用於測試和其他內部用途,不適用於生產 NDB Cluster 中。
您可以發出適當的查詢來取得更具體、更詳細或兩者兼具的輸出。此範例提供關於 NodeId
、NoOfReplicas
、HostName
、DataMemory
、IndexMemory
和 TotalSendBufferMemory
參數的所有可用資訊,這些資訊目前設定為叢集中所有資料節點的值
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
此查詢在用於簡單測試的 2 個資料節點小型 NDB Cluster 上執行時的輸出如下所示
*************************** 1. row ***************************
Name: NodeId
Node: 2
Type: unsigned
Default:
Minimum: 1
Maximum: 144
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: 144
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)