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Tair (Redis® OSS-Compatible):Manually increase the bandwidth of an instance

Last Updated:Jul 12, 2025

When your business is about to experience traffic spikes during promotional events such as flash sales, if the default bandwidth of your Tair (Redis OSS-compatible) instance is insufficient, you can manually increase the bandwidth without changing specifications to handle traffic spikes more effectively.

Function overview

Different instance specifications correspond to different bandwidth limits. If traffic exceeds the bandwidth limit, blocking may occur, affecting service performance. Compared to changing instance specifications, adjusting bandwidth helps you quickly increase capacity, reduce overall costs, and avoid connection interruptions, allowing for immediate use.

Scenarios

In the following scenarios, you can adjust the bandwidth of an instance to prevent network congestion and performance deterioration.

Expand to view detailed application scenarios

Application scenario

Description

Handle traffic spikes

You can adjust the bandwidth of the instance to handle traffic spikes during promotional events such as flash sales. After these events end, you can decrease the bandwidth to reduce costs.

Mitigate impacts on your business

If many read and write operations are performed on large keys within a short period, you can temporarily increase the bandwidth to mitigate impacts on your business and reserve time to process these operations.

Deal with request skew at low costs

If your cluster or read/write splitting instance has specific data shards or read replicas that are frequently accessed, their bandwidth usage may reach allocated limits while other components remain underutilized. In this case, you can increase the bandwidth of specific data shards or read replicas instead of increasing the bandwidth or changing the specifications of the entire instance.

Increase the bandwidth of a standard instance

If you have a standard instance with the highest specifications and its bandwidth does not meet your business requirements, you can increase the bandwidth without upgrading to a cluster instance. This lets you focus on business growth.

Billing

You are charged on an hourly basis based on the amount of additional bandwidth and usage duration. The pricing varies by region. For more information, see Billable items.

Note

You are not charged for the default bandwidth provided for the instance type. You are charged only for the extra bandwidth that you purchase.

Feature limitations

  • The bandwidth of an instance (or a shard) can be increased by up to six times the default bandwidth, but the increase cannot exceed 192 Mbit/s. For example, the default bandwidth of a 2 GB standard Tair memory-optimized instance is 96 Mbit/s. The bandwidth can be increased by up to 192 Mbit/s, resulting in a maximum bandwidth of 288 Mbit/s. The default bandwidth of a 256 MB standard Redis Community Edition instance is 10 Mbit/s. The bandwidth can be increased by up to 60 Mbit/s, resulting in a maximum bandwidth of 70 Mbit/s.

    If you need higher bandwidth, you can upgrade the specifications of your instance or upgrade the architecture (for example, from standard to cluster) to obtain higher bandwidth performance. For more information, see Instance specifications.

  • If you perform one of the following operations, the purchased extra bandwidth automatically becomes invalid and your money is refunded. You can re-increase the bandwidth for your instance as needed.

    Operation

    Exception

    Major version upgrade

    None

    Change the configurations of an instance

    If the instance uses the standard architecture, the bandwidth settings remain valid after you change the specifications of the instance.

    Change the zone of an instance

    If the instance is a standard instance, the bandwidth settings remain valid.

Procedure

  1. 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.

  2. In the Configuration Information section, click Modify to the right of Maximum Internal Bandwidth.

    Note
    • In the Configuration Information section, you can view the maximum internal bandwidth of the instance. If the instance is a cluster or read/write splitting instance, the bandwidth is the sum of the bandwidths that are allocated to all data nodes within the instance.

    • During off-peak hours, you can reduce the bandwidth to save resources and reduce costs. For more information about how to view the traffic usage of an instance, see View performance monitoring data.

  3. In the panel that appears, specify the amount of the extra bandwidth that you want to purchase and click OK.

    Key parameter

    Description

    Bandwidth

    The extra bandwidth that you want to purchase. The bandwidth of an instance can be increased up to six times the maximum bandwidth available for the instance type. For more information about the maximum bandwidths available for various instance types, see Overview. The extra bandwidth that you can select varies based on the instance type.

    • If the instance is a standard instance, adjust the bandwidth of the instance.

    • If the instance is a cluster or read/write splitting instance, select one of the following options:

      • Total Shard Bandwidth: allows you to adjust the bandwidths of all data shards within the instance at the same time. For example, if you want to handle traffic spikes during events such as flash sales, you can select this option to increase bandwidths.

      • Selected Shard Bandwidth: allows you to adjust the bandwidths of one or more specific data shards. For example, if you want to handle request skew issues, you can select this option to adjust the bandwidths of the selected data shards based on how requests are skewed.

        Note

        You can use the diagnostic report feature to analyze whether request skew issues occur on an instance. For more information, see Create a diagnostic report.

  4. Click Pay and complete the payment.

    After you complete the payment, wait for about 1 minute. Then, the maximum bandwidth of the instance is updated to the sum of the existing bandwidth and the extra bandwidth that you purchase.

    If you want to unsubscribe from the purchased extra bandwidth, you can adjust the bandwidth by following the preceding steps and then click Pay.

What to do next

  • We recommend that you use the bandwidth auto scaling feature. If you enable this feature, when the bandwidth usage of an instance reaches a specified threshold, the bandwidth is automatically increased or decreased. This feature reduces costs and facilitates O&M. For more information, see Enable bandwidth auto scaling.

  • If your instance is a Redis Community Edition instance and you need to increase the bandwidth by a large amount, we recommend that you use Tair (Enterprise Edition). The maximum bandwidth supported by each specification of Tair instances is 96 Mbit/s or higher.

Related API operation

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 is the maximum bandwidth limited to three times the default bandwidth?

    A: You may have purchased subscription bandwidth plans for the instance. Go to the My Orders page to find the corresponding order (the order ID is Instance ID-bw, for example, r-2zew****qs67bqho3n-bw), and unsubscribe from it. Then, follow the instructions in this topic to purchase pay-as-you-go bandwidth plans. This lets you increase the maximum bandwidth up to six times the default bandwidth of the instance.

  • Q: How do I adjust the bandwidth of a specific data shard or data node within a cluster or read/write splitting instance?

    A: When you adjust the bandwidth, you can select Multi-shard Bandwidth Adjustment and adjust the bandwidth of one or more specific shards as needed to flexibly handle skewed business traffic.

  • Q: Does a bandwidth adjustment cause transient connections?

    A: No, it is ready to use out of the box.

  • Q: How do I unsubscribe from the extra bandwidth that I purchase for my instance?

    A: Move the bandwidth adjustment slider to the leftmost position to decrease the bandwidth of your instance to the value provided for the instance type. Then, check the estimated cost and complete the payment.

  • Q: If I change the configurations of my instance after I purchase a specific amount of extra bandwidth, am I still charged for the extra bandwidth?

    A: If you change the configurations of a standard instance after you purchase extra bandwidth, the extra bandwidth remains valid and you are charged for it. The bandwidth of your instance is the sum of the bandwidth provided for the new instance type and the extra bandwidth you purchased. For other instance architectures, the extra bandwidth becomes invalid and you are no longer charged after you change the configurations. In this case, you must adjust the bandwidth again if needed. For information about bandwidth limits for each instance type, see Instance specifications.