# COST 6  How do you meet cost targets when you select resource type, size and number? Ensure that you choose the appropriate resource size and number of resources for the task at hand. You minimize waste by selecting the most cost effective type, size, and number. **Topics** + [ # COST06-BP01 Perform cost modeling ](cost_type_size_number_resources_cost_modeling.md) + [ # COST06-BP02 Select resource type, size, and number based on data ](cost_type_size_number_resources_data.md) + [ # COST06-BP03 Select resource type, size, and number automatically based on metrics ](cost_type_size_number_resources_metrics.md) # COST06-BP01 Perform cost modeling COST06-BP01 Perform cost modeling Identify organization requirements and perform cost modeling of the workload and each of its components. Perform benchmark activities for the workload under different predicted loads and compare the costs. The modeling effort should reflect the potential benefit. For example, time spent is proportional to component cost. **Level of risk exposed if this best practice is not established:** High ## Implementation guidance Implementation guidance Perform cost modeling for your workload and each of its components to understand the balance between resources, and find the correct size for each resource in the workload, given a specific level of performance. Perform benchmark activities for the workload under different predicted loads and compare the costs. The modelling effort should reflect potential benefit; for example, time spent is proportional to component cost or predicted saving. For best practices, refer to the *Review* section of the [Performance Efficiency Pillar whitepaper](https://docs.aws.amazon.com/wellarchitected/latest/performance-efficiency-pillar/review.html). [AWS Compute Optimizer](https://aws.amazon.com/compute-optimizer/) can assist with cost modelling for running workloads. It provides right-sizing recommendations for compute resources based on historical usage. This is the ideal data source for compute resources because it is a free service, and it utilizes machine learning to make multiple recommendations depending on levels of risk. You can also use [Amazon CloudWatch](https://aws.amazon.com/cloudwatch/) and [Amazon CloudWatch Logs](https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/WhatIsCloudWatchLogs.html) with custom logs as data sources for right sizing operations for other services and workload components. The following are recommendations for cost modelling data and metrics: + The monitoring must accurately reflect the end-user experience. Select the correct granularity for the time period and thoughtfully choose the maximum or 99th percentile instead of the average. + Select the correct granularity for the time period of analysis that is required to cover any workload cycles. For example, if a two-week analysis is performed, you might be overlooking a monthly cycle of high utilization, which could lead to under-provisioning. **Implementation steps ** + ** Perform cost modeling: **Deploy the workload or a proof-of-concept, into a separate account with the specific resource types and sizes to test. Run the workload with the test data and record the output results, along with the cost data for the time the test was run. Then redeploy the workload or change the resource types and sizes and re-run the test. ## Resources Resources **Related documents:** + [AWS Auto Scaling](https://aws.amazon.com/autoscaling/) + [Amazon CloudWatch features](https://aws.amazon.com/cloudwatch/features/) + [Cost Optimization: Amazon EC2 Right Sizing](https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/ce-rightsizing.html) + [AWS Compute Optimizer](https://aws.amazon.com/compute-optimizer/) # COST06-BP02 Select resource type, size, and number based on data COST06-BP02 Select resource type, size, and number based on data Select resource size or type based on data about the workload and resource characteristics. For example, compute, memory, throughput, or write intensive. This selection is typically made using a previous (on-premises) version of the workload, using documentation, or using other sources of information about the workload. **Level of risk exposed if this best practice is not established:** Medium ## Implementation guidance Implementation guidance Select resource size or type based on workload and resource characteristics, for example, compute, memory, throughput, or write intensive. This selection is typically made using cost modelling, a previous version of the workload (such as an on-premises version), using documentation, or using other sources of information about the workload (whitepapers, published solutions). **Implementation steps** + **Select resources based on data:** Using your cost modeling data, select the expected workload usage level, then select the specified resource type and size. ## Resources Resources **Related documents:** + [AWS Auto Scaling](https://aws.amazon.com/autoscaling/) + [Amazon CloudWatch features](https://aws.amazon.com/cloudwatch/features/) + [Cost Optimization: EC2 Right Sizing](https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/ce-rightsizing.html) # COST06-BP03 Select resource type, size, and number automatically based on metrics COST06-BP03 Select resource type, size, and number automatically based on metrics Use metrics from the currently running workload to select the right size and type to optimize for cost. Appropriately provision throughput, sizing, and storage for services such as Amazon Elastic Compute Cloud (Amazon EC2), Amazon DynamoDB, Amazon Elastic Block Store (Amazon EBS) (PIOPS), Amazon Relational Database Service (Amazon RDS), Amazon EMR, and networking. This can be done with a feedback loop such as automatic scaling or by custom code in the workload. **Level of risk exposed if this best practice is not established:** Low ## Implementation guidance Implementation guidance Create a feedback loop within the workload that uses active metrics from the running workload to make changes to that workload. You can use a managed service, such as [AWS Auto Scaling](https://aws.amazon.com/autoscaling/), which you configure to perform the right sizing operations for you. AWS also provides [APIs, SDKs](https://aws.amazon.com/developer/tools/), and features that allow resources to be modified with minimal effort. You can program a workload to stop-and-start an Amazon Elastic Compute Cloud(Amazon EC2) instance to allow a change of instance size or instance type. This provides the benefits of right-sizing while removing almost all the operational cost required to make the change. Some AWS services have built in automatic type or size selection, such as [Amazon Simple Storage Service(Amazon S3) Intelligent-Tiering](https://aws.amazon.com/about-aws/whats-new/2018/11/s3-intelligent-tiering/). Amazon S3 Intelligent-Tiering automatically moves your data between two access tiers: frequent access and infrequent access, based on your usage patterns. **Implementation steps** + ** Configure workload metrics: **Ensure you capture the key metrics for the workload. These metrics provide an indication of the customer experience, such as the workload output, and align to the differences between resource types and sizes, such as CPU and memory usage. + ** View rightsizing recommendations: **Use the rightsizing recommendations in AWS Compute Optimizer to make adjustments to your workload. + ** Select resource type and size automatically based on metrics: **Using the workload metrics, manually or automatically select your workload resources. Configuring AWS Auto Scaling or implementing code within your application can reduce the effort required if frequent changes are needed, and it can potentially implement changes sooner than a manual process. ## Resources Resources **Related documents:** + [AWS Auto Scaling](https://aws.amazon.com/autoscaling/) + [AWS Compute Optimizer](https://aws.amazon.com/compute-optimizer/) + [Amazon CloudWatch features](https://aws.amazon.com/cloudwatch/features/) + [CloudWatch Getting Set Up](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/GettingSetup.html) + [CloudWatch Publishing Custom Metrics](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/publishingMetrics.html) + [Cost Optimization: Amazon EC2 Right Sizing](https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/ce-rightsizing.html) + [Getting Started with Amazon EC2 Auto Scaling](https://docs.aws.amazon.com/autoscaling/ec2/userguide/GettingStartedTutorial.html) + [Amazon S3 Intelligent-Tiering](https://aws.amazon.com/about-aws/whats-new/2018/11/s3-intelligent-tiering/) + [Launch an EC2 Instance Using the SDK](https://docs.aws.amazon.com/sdk-for-net/v2/developer-guide/run-instance.html)