Increase instance bandwidth - Tair (Redis® OSS-Compatible)

Overview

Different instance specifications have different bandwidth limits. If your network traffic exceeds the bandwidth limit, requests may be blocked, which can affect service performance. Compared to changing the instance specification, adjusting the bandwidth is a faster and more cost-effective way to increase throughput without connection interruptions. The change is applied immediately without disrupting your service.

Use cases

You can adjust the bandwidth of your instance to handle the following use cases.

Detailed use cases

Use case	Description
Handle traffic spikes flexibly	If you anticipate a traffic surge from a promotional event like a flash sale, you can increase bandwidth for the event and then decrease it afterward to save on resources and costs.
Quickly mitigate the impact of bandwidth limits	If a sudden increase in read and write operations on large keys occurs, you can quickly increase bandwidth to prevent service disruption and allow time to address the underlying issue.
Address access skew cost-effectively	For an instance with a cluster architecture or read/write splitting architecture, some data shards or read replicas may experience high traffic and frequently hit their bandwidth limits, while others have low utilization. You can upgrade the bandwidth for only the specific data shards that need it, without upgrading the entire instance or changing its specification.
Go beyond the bandwidth limit of a standard architecture	If your instance uses the standard architecture and is already at the highest available specification, but the bandwidth is still insufficient for your business needs, you can increase the bandwidth beyond the default limit. This allows you to avoid upgrading to a cluster architecture and changing your existing implementation, so you can focus on your business.

Billing

You are charged hourly for any additional bandwidth. The price varies by region. For more information, see Billing items.

Note

The default bandwidth included with your instance is free of charge. You are only billed for the additional bandwidth you add.

Limitations

You can increase the bandwidth of an instance or a single data shard by up to 6x its default value, to a maximum increase of 192 MB/s. For example, a 2 GB Tair memory-optimized instance with a standard architecture has a default bandwidth of 96 MB/s. You can add up to 192 MB/s, for a total maximum bandwidth of 288 MB/s. A 256 MB Redis Open-Source Edition instance with a standard architecture has a default bandwidth of 10 MB/s. You can add up to 60 MB/s, for a total maximum bandwidth of 70 MB/s.

If you require more bandwidth, you can upgrade the instance specification or upgrade the instance architecture, for example, from a standard architecture to a cluster architecture. For more information, see Instance specifications and FAQ.

Performing one of the following operations automatically releases the purchased additional bandwidth and issues a refund. You must then add bandwidth again if your business requires it.

Operation	Exception
Major version upgrade	None.
Change the configurations of an instance	For instances with a standard architecture, upgrading only the specification preserves the additional bandwidth configuration.
Change the zone of an instance	For instances with a standard architecture, the bandwidth configuration remains valid.

Procedure

Log on to the console and go to the Instances page. In the top navigation bar, select the region in which the instance that you want to manage resides. Then, find the instance and click the instance ID.
In the Configuration Information section, click Bandwidth MB/s next to Modify.
Note
- On this page, you can view the current maximum bandwidth of the instance. If the instance has a cluster architecture or read/write splitting architecture, the value shown is the total maximum bandwidth of the instance, which is the sum of the bandwidth of all its data nodes.
- After a traffic peak has passed, you can also decrease the bandwidth to save costs and resources. To learn how to view the traffic usage of your instance, see View performance monitoring data.

In the panel that appears, set the additional bandwidth and click Determine.

Key parameter

Description

Adjust Bandwidth

The maximum bandwidth you can add is up to 6x the default value, capped at 192 MB/s. For details about the default bandwidth for each instance specification, see Instance specifications and FAQ. The available options vary based on the instance architecture.

Standard architecture: Directly adjust the total bandwidth for the instance.
Cluster architecture or read/write splitting architecture: You can select one of the following options:
- Adjust Bandwidth for All Shards: Increases or decreases the bandwidth for all data shards in the instance. This is useful for handling predictable traffic spikes, such as during a flash sale.
- Adjust Bandwidth for Individual Shards: Adjusts the bandwidth for one or more specific data shards. This is useful for resolving issues like access skew by increasing bandwidth only for the affected shards.
  Note
  - For a read/write splitting architecture, you can adjust the bandwidth only at the shard level. You cannot adjust the bandwidth for individual read replicas.
  - You can use the instance diagnosis feature to check for access skew. For more information, see Diagnose an instance.

Click Pay and complete the payment process.

The new maximum bandwidth takes effect in about one minute.

To cancel the additional bandwidth, you can repeat the procedure to set the additional bandwidth to 0 MB/s and click Pay to finalize the change.

Next steps

Consider using the burstable elastic bandwidth feature. When traffic exceeds the provisioned bandwidth, the system automatically adds extra bandwidth to ensure service stability. When traffic returns to normal, the extra bandwidth is automatically released. This feature helps reduce costs and improve operational efficiency.
To schedule bandwidth upgrades for your Tair instance, see Schedule temporary bandwidth upgrades for a Tair instance.
If you are using a Redis Open-Source Edition instance and need a significant bandwidth increase, we recommend upgrading to Tair (Enterprise Edition). All Tair (Enterprise Edition) instance specifications support a maximum bandwidth of 96 MB/s or higher.

API reference

API operation	Description
EnableAdditionalBandwidth	Adjusts the bandwidth of an instance.

FAQ

Q: Why can't I find the Maximum Bandwidth button?

A: Tair (Enterprise Edition) disk-based instances do not support modifying the default bandwidth.
Q: Why can I only increase the bandwidth to three times the default value?

A: Burstable bandwidth and Bandwidth Auto Scaling require a pay-as-you-go bandwidth plan. If your instance uses a subscription bandwidth plan, the maximum bandwidth can only be increased to 3 times the default bandwidth. To exceed this limit, unsubscribe from the subscription bandwidth plan and purchase a pay-as-you-go bandwidth plan. This allows you to increase the bandwidth by up to 6 times the original default bandwidth. To unsubscribe, go to the My Orders page, find the corresponding order (order ID: Instance ID-bw, for example, r-2zew****qs67bqho3n-bw), and cancel the subscription.
Q: For an instance with a cluster or read/write splitting architecture, how do I adjust the bandwidth for a specific shard or node?

A: When you modify the bandwidth, you can select Adjust Multi-Shard Bandwidth and individually adjust the bandwidth of a single shard or multiple shards based on your business needs to more flexibly handle skewed traffic.
Q: Does adjusting the instance bandwidth cause a transient connection error?

A: No. The change takes effect seamlessly without interrupting connections.
Q: How do I cancel the additional bandwidth I purchased?

A: You can perform the bandwidth adjustment operation again. Set the additional bandwidth to 0 MB/s (by moving the slider to the far left), and then complete the payment process. This action processes any applicable refunds.
Q: If I upgrade the instance specification after increasing its bandwidth, will I still be charged for the additional bandwidth?

A: For an instance with a standard architecture, the additional bandwidth setting is preserved after you upgrade the specification. The new total bandwidth will be the sum of the bandwidth for the new specification and your purchased bandwidth, and you will be billed accordingly. For instances with other architectures, upgrading the specification removes the additional bandwidth, and billing for it stops. You must add bandwidth again if required. For more information about bandwidth limits for each instance specification, see Instance specifications and FAQ.