You can create multiple instances of the same specifications in an ApsaraDB MyBase dedicated cluster by configuring resource overcommitment. This improves the CPU utilization of hosts and reduces costs. This topic describes how to configure resource overcommitment based on your requirements after you create dedicated clusters.

Background information

In industries such as gaming, the user growth trends of new services are unpredictable. If you purchase a great number of ApsaraDB RDS instances ahead of time, the instance resources may be wasted. In this case, you can use the resource overcommitment feature to create multiple instances of the same specifications on your hosts and monitor the performance of hosts.
  • If the number of users grows faster than expected, you can purchase additional hosts and migrate specific instances to the new hosts.
  • If the number of users grows slower than expected, you can configure resource overcommitment to meet business requirements and reduce resource costs.
Examples:
  • If you do not configure resource overcommitment, after you purchase one 32-core, 256 GB host, you can create four 8 cores and 64 GB instances on the host. The resources of these instances are isolated from each other.
  • If you set the CPU overcommit ratio to 200%, after you purchase one 32-core, 256 GB host, you can create eight 8 cores and 32 GB instances. If the number of users grows fast, you can add hosts later.

Set overcommit ratios after you create a dedicated cluster

After you create a dedicated cluster, you can set overcommit ratios based on host instance types and instance specifications.

  1. Log on to the ApsaraDB MyBase console.
  2. On the Dedicated Clusters page, find the dedicated cluster for which you want to set overcommit ratios and click Edit in the Actions column. The Edit Dedicated Cluster panel appears.
    Modify
  3. In the Edit Dedicated Cluster panel, specify CPU Overcommit Ratio, Storage Overcommit Ratio, and Maximum Memory Usage.
    • CPU Overcommit Ratio: the CPU overcommit ratio of the dedicated cluster. If you set this parameter to 200%, up to twice as many CPU resources can be allocated compared with the amount of resources provided. This maximizes the CPU utilization.
    • Storage Overcommit Ratio: the storage overcommit ratio of each host in the dedicated cluster.
    • Maximum Memory Usage: the maximum memory usage of each host in the dedicated cluster.
      Note Maximum Memory Usage can be modified only for ApsaraDB MyBase for MySQL dedicated clusters.
    Parameters
  4. Click OK. On the Dedicated Clusters page, find the dedicated cluster and click Details in the Actions column. On the Basic Information page, view the configuration information.
    Description
    Resource overcommitment

Scale out a dedicated cluster

To reduce workloads on your hosts, you can add hosts to your dedicated cluster and migrate specific instances to the new hosts. For more information about how to add hosts and migrate instances, see Create a host and Migrate an instance to another host.