This topic describes how to adjust the bandwidth of an ApsaraDB for Redis instance. If the bandwidth of an instance is insufficient to handle unexpected or scheduled traffic spikes, such as traffic spikes in a flash sale, you can increase the bandwidth of the instance without changing the instance specifications. This allows you to focus on business growth.
Prerequisites
The instance is deployed in classic mode.
The instance is a Community Edition instance or an Enhanced Edition (Tair) DRAM-based instance. For more information about DRAM-based instances, see DRAM-based instances.
Scenarios
The bandwidth of an instance varies based on the instance type. If the bandwidth in use reaches the allocated bandwidth, network congestion may occur and instance performance may deteriorate. In the following scenarios, you can adjust the bandwidth of an instance to prevent network congestion and performance deterioration on the instance. A bandwidth adjustment helps you increase bandwidth without transient connections at lower costs than an instance specification change.
We recommend that you use the bandwidth auto scaling feature. If you enable this feature, when the bandwidth usage of an instance reaches the 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 the instance is a Community Edition instance that requires a sharp bandwidth increase, we recommend that you change the instance into an Enhanced Edition (Tair) instance. This is because a Tair instance can support a bandwidth of 96 Mbit/s or more.
Scenario | Description |
Handle traffic spikes | You can adjust the bandwidth of the instance to handle traffic spikes during promotional events such as a flash sale. After these events end, you can decrease the bandwidth of the instance to reduce costs. |
Mitigate impacts on your business | If a large number of read and write operations are performed on large keys within a short period of time, you must temporarily increase the bandwidth of the instance to mitigate impacts on your business and to reserve time to process these operations. |
Deal with skewed requests at low costs | If your instance uses the cluster or read/write splitting architecture, specific data shards or read replicas of the instance are more frequently accessed than others. As a result, the bandwidth consumption of these data shards or read replicas frequently reaches the allocated bandwidths. However, the usage of the bandwidths that are allocated to other data shards or read replicas is low. In this case, you can increase the bandwidths of specific data shards or read replicas instead of increasing the bandwidth or changing the specifications of the instance. |
Increase the bandwidth of a standard instance | If the instance is a standard instance that has the highest specifications and the bandwidth of the instance does not meet your business requirements, you can increase the bandwidth of the instance without the need to upgrade the instance to a cluster instance. This allows you to focus on business improvement. For more information about standard instances, see Standard master-replica instances. |
Limits
The maximum bandwidth for an instance can be increased up to three times the bandwidth that is provided for the instance type. For example, the default bandwidth of a Tair 2 GB DRAM-based master-replica instance is 96 MB/s. In this case, the maximum bandwidth of the instance can be increased to up to 288 MB/s.
To further increase the bandwidth of the instance, you can change the instance configurations or instance architecture such as from the standard architecture to the cluster architecture. For more information, see Instance types.
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 based on your business requirements.
Operation
Exception
None
If the instance is a standard instance, the bandwidth settings remain valid after you change the specifications of the instance.
If the instance is a standard instance, the bandwidth settings remain valid.
Billing
You are charged per hour based on the amount and usage duration of the extra bandwidth that you purchase. The fees vary based on the region that you select. For more information, see Billable items.
You are not charged for the default bandwidth that is provided for the instance type. You are charged only for the extra bandwidth that you purchase.
Procedure
Log on to the ApsaraDB for Redis 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 Basic Information section, click Modify to the right of Maximum Internal Bandwidth.
NoteIn the Basic 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.
In the panel that appears, specify the amount of the extra bandwidth that you want to purchase.
Key parameter
Description
Bandwidth
The extra bandwidth that you want to purchase. The bandwidth of an instance can be increased up to three times the bandwidth that is provided for the instance type. For more information about the bandwidths that are provided 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, instead of changing the configurations of the instance.
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.
NoteYou can use the diagnostic report feature to analyze whether request skew issues occur on an instance. For more information, see Create a diagnostic report.
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.
FAQ
How do I adjust the bandwidth of a specific data shard or data node within a cluster or read/write splitting instance?
When you specify the extra bandwidth that you want to purchase, select Selected Shard Bandwidth. Then, you can adjust the bandwidth of a specific data shard or data node within a cluster or read/write splitting instance based on your business requirements. This way, you can handle request skew issues with more flexibility.
Does a bandwidth adjustment cause transient connections?
No, a bandwidth adjustment immediately takes effect and does not cause transient connections.
How do I unsubscribe from the extra bandwidth that I purchase for my instance?
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.
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?
If you change the configurations of your instance after you purchase a specific amount of extra bandwidth, the extra bandwidth remains valid and you are charged for the extra bandwidth. The bandwidth of your instance is the sum of the bandwidth that is provided for the new instance type and the extra bandwidth that you purchase. For other instance architectures, the extra bandwidth that you purchase becomes invalid and you are no longer charged for the bandwidth after you change the configurations of your instance. In this case, you must adjust the bandwidth of the instance again if needs arise. For more information about the bandwidth limits on various instance types, see Overview.
Related API operations
API operation | Description |
Adjusts the bandwidth of an ApsaraDB for Redis instance. |