Using Aurora Serverless v2 - Amazon Aurora
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Using Aurora Serverless v2

Aurora Serverless v2 is an on-demand, autoscaling configuration for Amazon Aurora. Aurora Serverless v2 helps to automate the processes of monitoring the workload and adjusting the capacity for your databases. Capacity is adjusted automatically based on application demand. You're charged only for the resources that your DB clusters consume. Thus, Aurora Serverless v2 can help you to stay within budget and avoid paying for computer resources that you don't use.

This type of automation is especially valuable for multitenant databases, distributed databases, development and test systems, and other environments with highly variable and unpredictable workloads.

Aurora Serverless v2 use cases

Many kinds of workloads can benefit from Aurora Serverless v2. Aurora Serverless v2 is especially useful for the following use cases:

  • Variable workloads – You're running workloads that have sudden and unpredictable increases in activity. An example is a traffic site that sees a surge of activity when it starts raining. Another is an e-commerce site with increased traffic when you offer sales or special promotions. With Aurora Serverless v2, your database automatically scales capacity to meet the needs of the application's peak load and scales back down when the surge of activity is over. With Aurora Serverless v2, you no longer need to provision for peak or average capacity. You can specify an upper capacity limit to handle the worst-case situation, and that capacity isn't used unless it's needed.

    The granularity of scaling in Aurora Serverless v2 helps you to match capacity closely to your database's needs. For a provisioned cluster, scaling up requires adding a whole new DB instance. For an Aurora Serverless v1 cluster, scaling up requires doubling the number of Aurora capacity units (ACUs) for the cluster, such as from 16 to 32 or 32 to 64. In contrast, Aurora Serverless v2 can add half an ACU when only a little more capacity is needed. It can add 0.5, 1, 1.5, 2, or additional half-ACUs based on the additional capacity needed to handle an increase in workload. And it can remove 0.5, 1, 1.5, 2, or additional half-ACUs when the workload decreases and that capacity is no longer needed.

  • Multi-tenant applications – With Aurora Serverless v2, you don't have to individually manage database capacity for each application in your fleet. Aurora Serverless v2 manages individual database capacity for you.

    You can create a cluster for each tenant. That way, you can use features such as cloning, snapshot restore, and Aurora global databases to enhance high availability and disaster recovery as appropriate for each tenant.

    Each tenant might have specific busy and idle periods depending on the time of day, time of year, promotional events, and so on. Each cluster can have a wide capacity range. That way, clusters with low activity incur minimal DB instance charges. Any cluster can quickly scale up to handle periods of high activity.

  • New applications – You're deploying a new application and you're unsure about the DB instance size you need. By using Aurora Serverless v2, you can set up a cluster with one or many DB instances and have the database autoscale to the capacity requirements of your application.

  • Development and testing – With Aurora Serverless v2, you can create Aurora Serverless v2 DB instances with a low minimum capacity instead of using T DB instance classes. You can set the maximum capacity high enough that those DB instances can still run substantial workloads without running low on memory. When the database isn't in use, all the DB instances scale down to avoid unnecessary charges.

    Tip

    To make it convenient to use Aurora Serverless v2 in development and test environments, the Amazon Web Services Management Console provides the Easy create shortcut when you create a new cluster. If you choose the Dev/Test option, Aurora creates a cluster with an Aurora Serverless v2 DB instance and a capacity range that's typical for a development and test system.

  • Mixed-use applications – Suppose that you have an online transaction processing (OLTP) application, but you periodically experience spikes in query traffic. By specifying promotion tiers for the Aurora Serverless v2 DB instances in a cluster, you can configure your cluster so that the reader DB instances can scale independently of the writer DB instance to handle the additional load. When the usage spike subsides, the reader DB instances scale back down to match the capacity of the writer DB instance.

  • Capacity planning – Suppose that you usually adjust your database capacity, or verify the optimal database capacity for your workload, by modifying the DB instance classes of all the DB instances in a cluster. With Aurora Serverless v2, you can avoid this administrative overhead. You can determine the appropriate minimum and maximum capacity by running the workload and checking how much the DB instances actually scale.

    You can modify existing DB instances from provisioned to Aurora Serverless v2 or from Aurora Serverless v2 to provisioned. You don't need to create a new cluster or a new DB instance in such cases.

    With an Aurora global database, you might not need as much capacity for the secondary clusters as in the primary cluster. You can use Aurora Serverless v2 DB instances in the secondary clusters. That way, the cluster capacity can scale up if a secondary region is promoted and takes over your application's workload.

Starting to use Aurora Serverless v2 for existing provisioned workloads

Suppose that you already have an Aurora application running on a provisioned cluster. You can check how the application would work with Aurora Serverless v2 by adding one or more Aurora Serverless v2 DB instances to the existing cluster as reader DB instances. You can check how often the reader DB instances scale up and down. You can use the Aurora failover mechanism to promote an Aurora Serverless v2 DB instance to be the writer and check how it handles the read/write workload. That way, you can switch over with minimal downtime and without changing the endpoint that your client applications use. For details on the procedure to convert existing clusters to Aurora Serverless v2, see Getting started with Aurora Serverless v2.

Advantages of Aurora Serverless v2

Aurora Serverless v2 is intended for variable or "spiky" workloads. With such unpredictable workloads, you might have difficulty planning when to change your database capacity. You might also have trouble making capacity changes quickly enough using the familiar mechanisms such as adding DB instances or changing DB instance classes. Aurora Serverless v2 provides the following advantages to help with such use cases:

  • Simpler capacity management than provisioned – Aurora Serverless v2 reduces the effort for planning DB instance sizes and resizing DB instances as the workload changes. It also reduces the effort for maintaining consistent capacity for all the DB instances in a cluster.

  • Faster and easier scaling during periods of high activity – Aurora Serverless v2 scales compute and memory capacity as needed, with no disruption to client transactions or your overall workload. The ability to use reader DB instances with Aurora Serverless v2 helps you to take advantage of horizontal scaling in addition to vertical scaling. The ability to use Aurora global databases means that you can spread your Aurora Serverless v2 read workload across multiple Amazon Web Services Regions. This capability is more convenient than the scaling mechanisms for provisioned clusters. It's also faster and more granular than the scaling capabilities in Aurora Serverless v1.

  • Cost-effective during periods of low activity – Aurora Serverless v2 helps you to avoid overprovisioning your DB instances. Aurora Serverless v2 adds resources in granular increments when DB instances scale up. You pay only for the database resources that you consume. Aurora Serverless v2 resource usage is measured on a per-second basis. That way, when a DB instance scales down, the reduced resource usage is registered right away.

  • Greater feature parity with provisioned – You can use many Aurora features with Aurora Serverless v2 that aren't available for Aurora Serverless v1. For example, with Aurora Serverless v2 you can use reader DB instances, global databases, Amazon Identity and Access Management (IAM) database authentication, and Performance Insights. You can also use many more configuration parameters than with Aurora Serverless v1.

    In particular, with Aurora Serverless v2 you can take advantage of the following features from provisioned clusters:

    • Reader DB instances – Aurora Serverless v2 can take advantage of reader DB instances to scale horizontally. When a cluster contains one or more reader DB instances, the cluster can fail over immediately in case of problems with the writer DB instance. This is a capability that isn't available with Aurora Serverless v1.

    • Multi-AZ clusters – You can distribute the Aurora Serverless v2 DB instances of a cluster across multiple Availability Zones (AZs). Setting up a Multi-AZ cluster helps to ensure business continuity even in the rare case of issues that affect an entire AZ. This is a capability that isn't available with Aurora Serverless v1.

    • Global databases – You can use Aurora Serverless v2 in combination with Aurora global databases to create additional read-only copies of your cluster in other Amazon Web Services Regions for disaster recovery purposes.

    • RDS Proxy – You can use Amazon RDS Proxy to allow your applications to pool and share database connections to improve their ability to scale.

  • Faster, more granular, less disruptive scaling than Aurora Serverless v1 – Aurora Serverless v2 can scale up and down faster. Scaling can change capacity by as little as 0.5 ACUs, instead of doubling or halving the number of ACUs. Scaling typically happens with no pause in processing at all. Scaling doesn't involve an event that you have to be aware of, as with Aurora Serverless v1. Scaling can happen while SQL statements are running and transactions are open, without the need to wait for a quiet point.