AnalyticDB for MySQL:Scale a Data Warehouse Edition cluster and change the cluster mode

Usage notes

Scale a cluster

• When you scale a cluster or change the performance level of enhanced SSDs (ESSDs) from PL1, PL2, or PL3 to PL0, you cannot execute the SUBMIT JOB statement to submit asynchronous jobs. If your business requires asynchronous jobs, scale your cluster during appropriate periods.

• When you scale a cluster, data in the cluster is migrated for redistribution. The amount of time that is required to migrate data is proportional to the data volume.

• When you downgrade cluster specifications, data migration may require up to dozens of hours to complete. Proceed with caution especially if your cluster contains a large amount of data.

• When the scaling process is about to end, your service may encounter transient connections. We recommend that you scale your cluster during off-peak hours or make sure that your application is configured to automatically reconnect to your cluster.

• If you change the ESSD performance level, you cannot change other configurations.

• When you change the ESSD performance level from PL1, PL2, or PL3 to PL0, data in the cluster is migrated for redistribution. The amount of time that is required to migrate data is proportional to the data volume. When you change the ESSD performance level to a higher level, data is not redistributed and the service is not affected.

Change the cluster mode

• You can change the cluster mode only for AnalyticDB for MySQL clusters of V3.1.3.9 or later.

  Note For information about how to query the minor version of a cluster, see How do I query the version of an AnalyticDB for MySQL cluster? To update the minor version of a cluster, contact technical support.

• When you change the cluster mode, you must apply for new cluster resources, perform full and incremental migration, and switch your business from the existing cluster to the new cluster. The amount of time that is required for the entire process varies based on the cluster specifications and data volume.

• During the switchover from the existing cluster to the new cluster, the existing cluster becomes read-only for a period of 5 to 10 minutes.

  After you connect to the existing cluster, execute the following statement to specify the time window for the switchover. In this example, the switchover is performed within a time window of 23:00 to 23:30.

  SET adb_config REPLICATION_SWITCH_TIME_RANGE=`23:00, 23:30`;

  For information about how to connect to an AnalyticDB for MySQL cluster, see Connect to an AnalyticDB for MySQL cluster.

• When a C32 cluster in reserved mode is changed to elastic mode, the specifications of a single node decrease to 8 cores. By default, BUILD jobs occupy 3 cores. In this case, the average CPU utilization increases. If the increased average CPU utilization does not affect your business, ignore this change. If your business is affected, upgrade your cluster or submit a ticket. For more information about BUILD jobs, see BUILD.

Billing rules

For information about the billing rules, see Billing of configuration changes.

Scale up a cluster

Scale down a cluster

Scale down a cluster in elastic mode

1. Log on to the AnalyticDB for MySQL console. In the upper-left corner of the console, select a region. In the left-side navigation pane, click Clusters. On the Data Warehouse Edition (V3.0) tab, find the cluster that you want to scale down and click Scale Down in the Actions column.

2. On the Upgrade/Downgrade page, set the Version parameter to Data Warehouse Edition (V3.0) or Data Lakehouse Edition (V3.0), configure the corresponding parameters, and then click Buy Now in the lower-right corner of the page.

   Data Warehouse Edition

   Parameter	Description
   Mode	The mode of the cluster. This parameter is automatically set to Elastic Mode. You do not need to configure this parameter.
   Edition	The edition of the cluster. This parameter is automatically set to Cluster Edition. You do not need to configure this parameter.
   Instance Type	The instance type of the cluster. This parameter is automatically set to E32. You do not need to configure this parameter.
   Computing Resources	The Computing Resources of the cluster. You can use computing resources to compute data. The increase in the amount of computing resources can accelerate data queries. We recommend that you select more CPU cores for computing resources than those for storage resources.
   ESSD Performance Level	The ESSD performance level of the cluster. ESSD performance levels provide the following capacities: PL0: 20 GiB to 65536 GiB. PL1: 20 GiB to 65536 GiB. PL2: 461 GiB to 65536 GiB. PL3: 1261 GiB to 65536 GiB. Important When you change the ESSD performance level, you cannot change other configurations. When you change the ESSD performance level, the amount of hot data in your cluster must reach the minimum capacity that can be provided by the selected performance level. The hot storage fee varies based on the ESSD performance level. You can calculate the hot storage fee by using the following formula: Unit storage price of an ESSD performance level × Hot storage size × Duration. For information about the unit storage price of each ESSD performance level, see Pricing for Data Warehouse Edition (V3.0).
   EIU Capacity	The single-node specifications of an elastic I/O unit (EIU) for the cluster. Each EIU consists of three nodes. Elastic I/O resources are bundled into units and sold as EIUs. You can use EIUs to scale up storage resources for clusters in elastic mode for Cluster Edition. For more information, see Use EIUs to scale up storage resources. After you scale up elastic I/O resources, the amount of hot data that is locked by each EIU increases. For more information, see the "EIU-based storage performance metrics" section of the Use EIUs to scale up storage resources topic. If you want to scale down the elastic I/O resources, you must make sure that the amount of hot data in your cluster is less than the amount of hot data that can be locked by EIU specifications after scale-down. If the preceding requirement cannot be met, we recommend that you migrate part of the data to cold storage before you scale down the elastic I/O resources.
   EIUs	The number of EIUs. Note This parameter takes effect only when the Mode parameter is set to Elastic Mode and the Computing Resources parameter is set to 32 cores and 128 GB or more.

   Data Lakehouse Edition

   Parameter	Description
   Reserved Computing Resources	The reserved computing resources of the cluster. You can use reserved computing resources to compute data. The increase in the amount of computing resources can accelerate data queries. If you require AnalyticDB for MySQL internal tables, the amount of reserved computing resources must be greater than 0 AnalyticDB compute units (ACUs). If the amount of reserved computing resources is 0 ACUs, you can use only external tables. If you set the Reserved Computing Resources parameter to 0 ACUs when you create a cluster, you can purchase reserved computing resources by scaling up the cluster. For more information, see Scale up or down a Data Lakehouse Edition cluster.
   Default Allocation Behavior	Specifies whether to allocate all reserved computing resources to the user_default resource group. After you create a cluster, you can modify the amount of reserved computing resources for the user_default resource group on the Resource Management page. Valid values: Yes: allocates all reserved computing resources to the user_default resource group. You can use the user_default resource group to create tables, write data, and query data. No: does not allocate reserved computing resources to the user_default resource group. You cannot use the resource group to create tables, write data, or query data. You must allocate resources to the resource group or create another resource group.
   Reserved Storage Resources	The reserved storage resources of the cluster. You can use reserved storage resources to store hot data. A set of reserved storage resources is equal to 24 ACUs and can store up to 4 TB of hot data. Important If you set the Reserved Computing Resources parameter to 0 ACUs, you must set the Reserved Storage Resources parameter to 0 ACUs. If you cannot determine the amount of required reserved storage resources when you create a cluster, you can set the Reserved Storage Resources parameter to 0 ACUs, and then purchase reserved storage resources based on your business requirements by scaling up the cluster. For more information, see Scale up or down a Data Lakehouse Edition cluster. You are billed for hot data storage based on the actual storage space that is occupied. For more information, see Billable items of Data Lakehouse Edition (V3.0).

3. For a subscription cluster, read and select the Terms of Service, and then click Buy Now. Confirm the order and the payment method, and then click Subscribe. For a pay-as-you-go cluster, read and select the Terms of Service, and then click Buy Now.

Scale down a cluster in reserved mode

1. Log on to the AnalyticDB for MySQL console. In the upper-left corner of the console, select a region. In the left-side navigation pane, click Clusters. On the Data Warehouse Edition (V3.0) tab, find the cluster that you want to scale down and click Scale Down in the Actions column.

2. On the Upgrade/Downgrade page, set the Version parameter to Data Warehouse Edition (V3.0) or Data Lakehouse Edition (V3.0), configure the corresponding parameters, and then click Buy Now in the lower-right corner of the page.

   Data Warehouse Edition

   Parameter	Description
   Version	The version of the cluster. This parameter is automatically set to Data Warehouse Edition (V3.0). You do not need to configure this parameter.
   Edition	The edition of the cluster. This parameter is automatically set to Cluster Edition. You do not need to configure this parameter.
   Instance Type	The instance type of the cluster.
   Node Groups	The number of node groups. By default, each node group consists of three nodes.
   Capacity	The storage of a single node group. If you purchase multiple node groups, you can calculate the total storage of the cluster by using the following formula: Total storage = Storage per node group × Number of node groups.
   ESSD Performance Level	The ESSD performance level of the cluster. ESSD performance levels provide the following capacities: PL0: 20 GiB to 65536 GiB. PL1: 20 GiB to 65536 GiB. Important When you change the ESSD performance level, you cannot change other configurations. When you change the ESSD performance level, the amount of hot data in your cluster must reach the minimum capacity that can be provided by the selected performance level. The hot storage fee varies based on the ESSD performance level. You can calculate the hot storage fee by using the following formula: Unit storage price of an ESSD performance level × Hot storage size × Duration. For information about the unit storage price of each ESSD performance level, see Pricing for Data Warehouse Edition (V3.0).

   Data Lakehouse Edition

   Parameter	Description
   Reserved Computing Resources	The reserved computing resources of the cluster. You can use reserved computing resources to compute data. The increase in the amount of computing resources can accelerate data queries. If you require AnalyticDB for MySQL internal tables, the amount of reserved computing resources must be greater than 0 AnalyticDB compute units (ACUs). If the amount of reserved computing resources is 0 ACUs, you can use only external tables. If you set the Reserved Computing Resources parameter to 0 ACUs when you create a cluster, you can purchase reserved computing resources by scaling up the cluster. For more information, see Scale up or down a Data Lakehouse Edition cluster.
   Default Allocation Behavior	Specifies whether to allocate all reserved computing resources to the user_default resource group. After you create a cluster, you can modify the amount of reserved computing resources for the user_default resource group on the Resource Management page. Valid values: Yes: allocates all reserved computing resources to the user_default resource group. You can use the user_default resource group to create tables, write data, and query data. No: does not allocate reserved computing resources to the user_default resource group. You cannot use the resource group to create tables, write data, or query data. You must allocate resources to the resource group or create another resource group.
   Reserved Storage Resources	The reserved storage resources of the cluster. You can use reserved storage resources to store hot data. A set of reserved storage resources is equal to 24 ACUs and can store up to 4 TB of hot data. Important If you set the Reserved Computing Resources parameter to 0 ACUs, you must set the Reserved Storage Resources parameter to 0 ACUs. If you cannot determine the amount of required reserved storage resources when you create a cluster, you can set the Reserved Storage Resources parameter to 0 ACUs, and then purchase reserved storage resources based on your business requirements by scaling up the cluster. For more information, see Scale up or down a Data Lakehouse Edition cluster. You are billed for hot data storage based on the actual storage space that is occupied. For more information, see Billable items of Data Lakehouse Edition (V3.0).