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Torch Object Storage

Quality of Service (QoS) policies

Creating QoS policies

TOS allows you to customize a QoS policy in the visual or JSON view. This topic explains how to do so.

Notes

The total JSON description size of QoS policies per account cannot exceed 20 KB.

A single Statement can have at most ten resources or principals.

If a request matches multiple QoS policies, all of the policies take effect. In this case, if the policies have the same type of QoS restriction, the restriction with the lowest quota applies.

A QoS policy defines the bandwidth limit for specific resources under specific conditions within a region. Burst bandwidth, on the other hand, is an account's flexible upper limit at the regional level. These two concepts operate at different levels and take effect concurrently.

For example, if an account’s intranet download bandwidth in China (Guangzhou) is 10 Gbps and its burst bandwidth is 5 Gbps, then the total intranet download bandwidth is 15 Gbps. At this time:

If you set a QoS policy for the "my-data" bucket under this account that limits the maximum intranet read bandwidth to 2 Gbps, the system allows the "my-data" bucket a maximum intranet read bandwidth of 2 Gbps.

If you set a QoS policy for the "my-data" bucket that limits its maximum intranet read bandwidth to 20 Gbps but the account’s total intranet download bandwidth quota is 15 Gbps, the system will allow the "my-data" bucket a maximum intranet read bandwidth of 15 Gbps.

By default, the owner of an account has full permissions. IAM users have no permissions by default. If an IAM user needs to perform any of the following operations, the account owner must grant the user the appropriate permissions using an IAM or bucket policy.

Set QoS policies: tos:PutQosPolicy

View QoS policy configurations: tos:GetQosPolicy

Delete QoS policies: tos:DeleteQosPolicy

Creating a QoS policy in visual view

In the left navigation pane, select Flow control management > QoS policy management.

At the top left of the QoS policy management page, select the target region.

On the Visual view tab, click Create policy.

On the Create QoS policy page, set the following parameters.

Parameter	Description
Policy configuration method	Select Visual view.
Policy name	Enter a name for the policy. The policy name must: Be unique. Contain only uppercase and lowercase letters, numbers, hyphens (-), underscores (_), periods (.), colons (:) and percent signs (%). Be between 1 and 255 characters long. If this parameter is not specified, TOS will automatically generate a name.
Policy Type	Select a throttling scheme for the QoS policy: Threshold traffic control: Uses flexible combinations of identity dimensions and resource scopes to throttle traffic to TOS resource groups. This enables isolation between multiple workloads. Priority traffic control: Adds multiple priority levels and guaranteed quotas to threshold-based throttling, ensuring the stable operation of core services while maximizing resource utilization.
QoS value	Set the throttling limits for the QoS policy. Options: WritesQPS: The QPS limit for write requests. Enter a positive integer. ReadsQPS: The QPS limit for read requests. Enter a positive integer. ListQPS: The QPS limit for list requests. Enter a positive integer. WritesRate: The upload bandwidth limit in Mbps. Enter a positive integer. ReadsRate: The download bandwidth limit in Mbps. Enter a positive integer. FetchQps: The QPS limit for synchronous fetches. Enter a positive integer. FetchRate: The bandwidth limit for synchronous fetches in Mbps. Enter a positive integer. AsyncFetchQPS: The QPS limit for asynchronous fetches. Enter a positive integer. AsyncFetchRate: The bandwidth limit for asynchronous fetches in Mbps. Enter a positive integer. tip For limits on read/write requests and bandwidth for each region per account, see Constraints and limitations.
Priority	The QoS policy's priority level follows these rules: It takes natural numbers starting from 1, and they must be consecutive and unique. For example, 1/2 and 1/2/3 are supported, but 1/3 is not. At least 2 and at most 3 priority levels must be configured. A higher number indicates a higher priority. tip This parameter only applies when the Policy Type is set to Priority traffic control. After you add priority configurations, the system automatically assigns the priority values. You do not need to enter them manually. You can click Move up or Move down in the Actions column to adjust priorities.
Guaranteed flow control value	Reserve a minimum amount of resources for a priority level. Even when the system is fully loaded, this level is guaranteed to receive this amount or more. This value follows the same rules as the QoS value parameter. tip This parameter only applies when the Policy Type is set to Priority traffic control. Each priority level must be assigned a guaranteed quota greater than 0. In other words, a guaranteed quota must be assigned to each additional priority level. The sum of the guaranteed quotas for all priority levels must be less than or equal to the total quota.
Authorized user	Specified account: The policy only applies to the specified account(s). Options: Current main account: The policy applies to one or more IAM users (subusers) or roles within the current account. The account ID is displayed by default. Click Add row to select IAM users or roles from the dropdown menu. Other main account: The policy applies to another account and its IAM users (subusers) or roles. Enter the account ID and IAM username(s) or rolename(s). All users: The policy applies to all users, including anonymous users.
User Policy	Select whether to include or exclude the specified user(s). The options are explained below. Include the above users: The policy applies to authorized users. Exclude the above users: The policy applies to all users except authorized users. tip User Policy cannot be set to Exclude the above users when Authorized user is set to All users.
Resource scope	All buckets: The policy takes effect on all buckets. Objects in bucket: The policy takes effect on a specific bucket. Select a bucket and specify the resource scope further: All objects: All objects within the bucket. Specified object(s): Specific object(s) within the bucket. If you select Specified object(s), click Add resource path to enter the prefix for the specified object(s). tip The resource scope covers all buckets if both All buckets and Objects in bucket are selected under Resource.
Resource strategy	Select whether to include or exclude the specified resource(s). The options are explained below. Include the above resources: The policy applies to the specified resources. Exclude the above resources: The policy applies to all resources except those specified. tip Resource strategy cannot be set to Exclude the above resources when Resource scope is set to All buckets.
Condition	Click the Add row icon and set the condition and value. For more information, see Conditions.

After completing the settings, click Next step.

After verifying the details, click Confirm.

Creating a QoS policy in JSON view

In the left navigation pane, select Flow control management > QoS policy management.

At the top left of the QoS policy management page, select the target region.

Click the JSON view tab.

Click Edit and enter the policy content. For more information on QoS policy parameters, see Parameters.

Threshold‑based throttling example:

The following statement establishes a 5,000 Mbps upload bandwidth limit for user "aaa" on the "bucketname" bucket.

{
"Statement": [
{
"Sid": "test",
"Quota": {
"WritesQps": "",
"ReadsQps": "",
"ListQps": "",
"WritesRate": "5000",
"ReadsRate": "",
"FetchQps": "",
"FetchRate": "",
"AsyncFetchQps": "",
"AsyncFetchRate": ""
},
"Principal": [
"trn:iam::214748****:user/aaa"
],
"Resource": "trn:tos:::bucketname/*"
}
]
}

Priority‑based throttling example:

The following statement sets the upload bandwidth limit for user "aaa" to 5,000 Mbps for buckets "bucket1", "bucket2", and "bucket3". "bucket1" has priority 1 and a guaranteed upload bandwidth of 1,000 Mbps. "bucket2" has priority 2 and a guaranteed upload bandwidth of 1,000 Mbps. "bucket3" has priority 3 and a guaranteed upload bandwidth of 3,000 Mbps.

{
"Statement": [
{
"Sid": "test-qos-policy",
"Quota": {
"WritesRate": "5000"
},
"Priority": [
{
"PriorityLevel": 3,
"GuaranteedQuota": {
"WritesRate": "3000"
},
"Principal": [
"trn:iam::200000:user/aaa"
],
"Resource": "trn:tos:::bucket3/*"
},
{
"PriorityLevel": 2,
"GuaranteedQuota": {
"WritesRate": "1000"
},
"Principal": [
"trn:iam::200000:user/aaa"
],
"Resource": "trn:tos:::bucket2/*"
},
{
"PriorityLevel": 1,
"GuaranteedQuota": {
"WritesRate": "1000"
},
"Principal": [
"trn:iam::200000:user/aaa"
],
"Resource": "trn:tos:::bucket1/*"
}
]
}
]
}

Save your settings by clicking Save.

Related operations

Edit a QoS policy

On the QoS policy management page, click the Visual view tab and then click Edit in the Actions column of the relevant policy. This will take you to the editing page where you can modify the policy.

Copy a QoS policy

On the QoS policy management page, find the Visual view tab and click ... > Copy in the Actions column of the relevant policy. On the Create QoS policy page, verify that the policy details are correct, and then click Next step and Confirm.

Delete a QoS policy

On the QoS policy management page, click the Visual view tab. In the Actions column of the relevant policy, click Delete. Then, confirm the deletion by clicking Delete in the box that appears.

Last updated: 2026.08.20 17:53:16