Scaling disk, memory, and CPU

Review current resources and hosting model

In the Resources tab, you find both Hosting model and Resource allocations tiles. These tiles reflect your current resources and hosting model. Select Configure to adjust the settings in each tile.

Scaling in the UI

In the Resources tab of the UI, select Configure on the Resource allocations tile. This opens up a panel where you can adjust your resources.

If your database is on the Isolated Compute hosting model, you then see a "Host sizes" table, where you can select the vCPU and RAM configuration per member for your database.

If you are on the Shared Compute hosting model, you see the Small configuration, providing 0.5 vCPU and 4 GB RAM per member; the Small Custom option; or Custom configuration. Small Custom indicates that your database was scaled with the CLI, API, or Terraform, which provides more fine-grained resource scaling, along with an option for automatically allocated vCPU pro-rated against RAM value. On the UI, you can scale to Small and Custom, but are not be able to scale to the fine-grained values provided by the CLI, API, or Terraform. With Custom, drag the slider or adjust the value in the input box to select your database's per member vCPU and RAM values.

The "Disk (GB/member)" slider is your disk selection per member. Drag the slider or adjust the number in the input box to change the number of GB disk. Note that Disk is tied to IOPS at 1 GB = 10 IOPS.

Members is the number of members of your database. For MongoDB, members are set to 3.

Review your total estimated cost in the calculator on the bottom. Note that if you have grandfathered costs, also known as legacy pricing structure, scaling your database instance removes some or all of your legacy pricing. For more information on grandfathering and when it ends, see Hosting model transition timeline.

After you are done, click Apply changes to trigger the scaling operation.

Switch to and between hosting models in the UI

In the Resources tab of the UI, select Configure on the Hosting model tile. This opens up a panel where you can adjust your hosting model selection.

The first option available is Select your hosting model. Here, you can switch to a different hosting model.

Below, you see the options to also adjust the resources of the new hosting model you've selected. Follow the instructions in the previous section, "Scaling in the UI" to adjust your resources.

Clicking Apply changes triggers this scale operation.

Review current resources and hosting model

IBM Cloud CLI cloud databases plug-in supports viewing and scaling the resources on your deployment. Use the command cdb deployment-groups to see current resource information for your service, including which resource groups are adjustable. To scale any of the available resource groups, use cdb deployment-groups-set command.

For example, with the following command you can view the resource groups for a deployment named "example-deployment". Note that this command will also reveal if your database is a Shared Compute or Isolated Compute instance through the hostflavor attribute. If the hostflavor is null, it is on an old style hosting model.

ibmcloud cdb deployment-groups <INSTANCE_NAME_OR_CRN>

This command produces the output:

Group   member
Count   3
|
+   Memory
|   Allocation                      6144mb
|   Allocation per member           2048mb
|   Minimum                         6144mb
|   Step Size                       256mb
|   Adjustable                      true
|   Cpu Enforcement Ratio Ceiling   49152mb
|   Cpu Enforcement Ratio           8192mb

|
+   CPU
|   Allocation              0
|   Allocation per member   0
|   Minimum                 6
|   Step Size               2
|   Adjustable              true
|                           
+   HostFlavor    
|   ID            multitenant
|   Name          
|   HostingSize   
|
+   Disk
|   Allocation              30720mb
|   Allocation per member   10240mb
|   Minimum                 30720mb
|   Step Size               2048mb
|   Adjustable              true

The deployment has three members, with 6144 MB of RAM and 30720 MB of disk allocated in total. The "per member" allocation is 2048 MB of RAM and 10240 MB of disk. The minimum value is the lowest the total allocation that can be set. The step size is the smallest amount by which the total allocation can be adjusted.

Resources and scaling in the CLI

The cdb deployment-groups-set command allows either the total RAM or total disk allocation to be set in MB. For example, to scale the memory of the "example-deployment" to 4096 MB of RAM for each memory member (for a total memory of 12288 MB), you use the command:

ibmcloud cdb deployment-groups-set <INSTANCE_NAME_OR_CRN> member --memory 12288

Determine the hosting model of your database

Use the following command to review the value of the hostflavor attribute. This will be null if the database is on a deprecated hosting model (not Shared or Isolated Compute).

ibmcloud cdb groups <deployment_id> --json

Switching to and between Hosting Models in the CLI

If your database is a Shared Compute instance, you can adjust the memory, CPU, and disk options with the following command. If your database is not on Shared Compute, this command will also move a database from a different hosting model to the Shared Compute hosting model.

ibmcloud cdb deployment-groups-set <deploymentid> <groupid> [--memory <val>] [--cpu <val>] [--disk <val>] [--hostflavor multitenant]

For example, use the following to scale to a Shared Compute instance or scale up your Shared Compute instance:

ibmcloud cdb deployment-groups-set crn:abc ... xyz:: member  --memory 24576 --cpu 6  --hostflavor multitenant

If your database is an Isolated Compute instance, memory and CPU are adjusted together by selecting the Isolated Compute size (see all sizes in Table 1). Disk is scaled separately. If your database is not on Isolated Compute, this command will also move a database from a different hosting model to the Isolated Compute hosting model.

Note that since the host flavor selection includes CPU and RAM sizes (b3c.4x16.encrypted is 4 CPU and 16 RAM), this request does not accept both an Isolated size selection and separate CPU and RAM allocation selections.

ibmcloud cdb deployment-groups-set <deploymentid> <groupid> [--disk <val>] [--hostflavor <hostflavor>]

For example, use the following to scale to an Isolated Compute instance or scale up your Isolated Compute instance:

ibmcloud cdb deployment-groups-set crn:abc ... xyz:: member  --hostflavor b3c.8x32.encrypted

CPU and RAM autoscaling is not supported on Cloud Databases Isolated Compute. Disk autoscaling is available. If you provisioned an isolated instance or switched over from a deployment with autoscaling, monitor your resources using IBM Cloud® Monitoring integration, which provides metrics for memory, disk space, and disk I/O utilization. To add resources to your instance, manually scale your deployment.

Review current resources and hosting model

The Foundation endpoint that is shown on the Overview panel of your service provides the base URL to access this deployment through the API. Use it with the /groups endpoint if you need to manage or automate scaling programmatically.

To view the current and scalable resources on a deployment, use the /deployments/{id}/groups endpoint. Note that this command will also reveal if your database is a Shared Compute or Isolated Compute instance through the host_flavor attribute. If the host_flavor is null, it is on an old style hosting model.

curl -X GET https://api.{region}.databases.cloud.ibm.com/v5/ibm/deployments/{id}/groups -H 'Authorization: Bearer <>' \

Scaling with the API

To scale the memory of a deployment to 4096 MB of RAM for each memory member (for a total memory of 12288 MB), use the following command:

curl -X PATCH https://api.{region}.databases.cloud.ibm.com/v5/ibm/deployments/{id}/groups/member 
-H 'Authorization: Bearer <>' 
-H 'Content-Type: application/json' 
-d '{"memory": {"allocation_mb": 12288}}' \

For more information, see the API reference.

Determine the hosting model of your database

Use the following command to review the value of the host_flavor attribute. This will be null if the database is on a deprecated hosting model (not Shared or Isolated Compute).

curl -X GET https://api.{region}.databases.cloud.ibm.com/v5/ibm/deployments/{id}/groups 
-H 'Authorization: Bearer <>' \

Switching to and between Hosting Models in the API

To scale any Cloud Databases Shared Compute instance, use the the following command, setting host_flavor to multitenant. If your database is not on Shared Compute, this command will also move a database from a different hosting model to the Shared Compute hosting model.

curl -X PATCH https://api.{region}.databases.cloud.ibm.com/v5/ibm/deployments/{id}/groups/member
-H 'Authorization: Bearer <>'
-H 'Content-Type: application/json'
-d '{"host_flavor": {"id": "multitenant"},
     "cpu": {"allocation_count": 3},
     "memory": {"allocation_mb": 12288}
    }' \

To scale any instance into a Cloud Databases Isolated Compute instance or to scale to a different Isolated Compute size, use the host_flavor parameter, this time set to the desired Isolated Compute size. Available hosting sizes and their host_flavor value parameters are listed in Table 1. For example, {"host_flavor": "b3c.4x16.encrypted"}. Note that since the host flavor selection includes CPU and RAM sizes (b3c.4x16.encrypted is 4 CPU and 16 RAM), this request does not accept both, an Isolated size selection and separate CPU and RAM allocation selections. Scale with the Cloud Databases API scaling endpoint, with a command like:

curl -X PATCH https://api.{region}.databases.cloud.ibm.com/v5/ibm/deployments/{id}/groups/member
-H 'Authorization: Bearer <>'
-H 'Content-Type: application/json'
-d '{"host_flavor": {"id": "b3c.4x16.encrypted"}}' \

CPU and RAM allocation is not allowed when provisioning or scaling through Isolated Compute. Specify mulitenant for the host_flavor parameter to have independent CPU and RAM selections.

CPU and RAM autoscaling is not supported on Cloud Databases Isolated Compute. Disk autoscaling is available. If you have provisioned an Isolated instance or switched over from a deployment with autoscaling, keep an eye on your resources using IBM Cloud® Monitoring integration, which provides metrics for memory, disk space, and disk I/O utilization. To add resources to your instance, manually scale your deployment.

Review current resources and hosting model

Review resource allocations to your database by checking your terraform scripts for cpu { allocation_count = }, memory {allocation_mb = }, and disk { allocation_mb = }. Review the host_flavor setting to determine if your database is a Shared Compute or Isolated Compute style hosting model. If host_flavor does not exist, your database is on an old style hosting model.

Scaling with Terraform

Before executing a Terraform script on an existing instance, use the terraform plan command to compare the current infrastructure state with the desired state defined in your Terraform files. Any alteration to the resource_group_id, service plan, version, key_protect_instance, key_protect_key, backup_encryption_key_crn attributes recreates your instance. For a list of current argument references with the Forces new resource specification, see the ibm_database Terraform Registry.

Scale your instance by adjusting your Terraform script for the resource you're interested in. In the following example, cpu, memory, and disk allocations are specified. Note that if you have a host flavor selected (Isolated Compute or Shared Compute Multitenant), keep the host flavor selection in your script.

To implement your change, run terraform apply.

data "ibm_resource_group" "group" {
  name = "<your_group>"
}
resource "ibm_database" "<your_database>" {
  name              = "<your_database_name>"
  plan              = "standard"
  location          = "eu-gb"
  service           = "databases-for-mongodb"
  resource_group_id = data.ibm_resource_group.group.id
  tags              = ["tag1", "tag2"]
  adminpassword     = "password12"
  group {
    group_id = "member"
    cpu {
      allocation_count = 6
    }
    memory {
      allocation_mb = 24576
    }
    disk {
      allocation_mb = 256000
    }
  }
  users {
    name     = "user123"
    password = "password12"
  }
  allowlist {
    address     = "172.168.1.1/32"
    description = "desc"
  }
}
output "ICD MongoDB database connection string" {
  value = "http://${ibm_database.test_acc.ibm_database_connection.icd_conn}"
}

Switching to and Scaling Hosting Models in Terraform

Select the hosting model you want your database to be scaled to. You can change this later.

To scale your Databases for MongoDB instance to the Shared Compute hosting flavor, set the "host_flavor" parameter to multitenant. This works if you want to scale to the Shared Compute hosting flavor, or if you want to keep the host flavor and scale your resources. To implement your change, run terraform apply.

See the following example:

data "ibm_resource_group" "group" {
  name = "<your_group>"
}
resource "ibm_database" "<your_database>" {
  name              = "<your_database_name>"
  plan              = "standard"
  location          = "eu-gb"
  service           = "databases-for-mongodb"
  resource_group_id = data.ibm_resource_group.group.id
  tags              = ["tag1", "tag2"]
  adminpassword     = "password12"
  group {
    group_id = "member"
    host_flavor {
      id = "multitenant"
    },
    cpu {
      allocation_count = 6
    }
    memory {
      allocation_mb = 24576
    }
    disk {
      allocation_mb = 256000
    }
  }
  users {
    name     = "user123"
    password = "password12"
  }
  allowlist {
    address     = "172.168.1.1/32"
    description = "desc"
  }
}
output "ICD MongoDB database connection string" {
  value = "http://${ibm_database.test_acc.ibm_database_connection.icd_conn}"
}

Scale your Databases for MongoDB instance to Isolated Compute with the same "host_flavor" parameter, set to the desired Isolated size. This command works to scale your database instance to a different Isolated Compute size, as well as to move from another host flavor to the Isolated Compute host flavor. Available hosting sizes and their host_flavor value parameters are listed in Table 1. For example, {"host_flavor": "b3c.4x16.encrypted"}. Note that since the host flavor selection includes CPU and RAM sizes (b3c.4x16.encrypted is 4 CPU and 16 RAM), this request does not accept both an Isolated size selection and separate CPU and RAM allocation selections.

To implement your change, run terraform apply.

data "ibm_resource_group" "group" {
  name = "<your_group>"
}
resource "ibm_database" "<your_database>" {
  name              = "<your_database_name>"
  plan              = "standard"
  location          = "eu-gb"
  service           = "databases-for-mongodb"
  resource_group_id = data.ibm_resource_group.group.id
  tags              = ["tag1", "tag2"]
  adminpassword     = "password12"
  group {
    group_id = "member"
    host_flavor {
      id = "b3c.8x32.encrypted"
    }
    disk {
      allocation_mb = 256000
    }
  }
  users {
    name     = "user123"
    password = "password12"
  }
  allowlist {
    address     = "172.168.1.1/32"
    description = "desc"
  }
}
output "ICD MongoDB database connection string" {
  value = "http://${ibm_database.test_acc.ibm_database_connection.icd_conn}"
}