What is right-sizing in the Cloud context?  Right-sizing for the Cloud could be defined as a process of planning for “the use of electronic capacities purchased, effectively and efficiently.” The term “right-size” is positive metric and demonstrates tight control on resource use. The purpose is to derive optimal benefit from optimal use of electronic capacities.

Right-sizing for Cloud computing begins with data trending analysis. A trend can be defined as a repeated measurement of data volumes over time. Trending can be used to study the inflow and outflow of data in a storage system. Data may flow into a system continuously or as per a pre-defined schedule for storage, access, and processing. The inflow of data adds to the stored volume. But, stored volumes are not static. Archival of data or deletion of data results in depletion of data volumes in storage. So, any trend analysis of data in storage must include both inflows and outflow volumes.

Identifying growth patterns and estimating data growth volumes is the next step in right-sizing. As the business grows and expands, the amount of data that is generated by the business is expected to grow. Growth trends can be estimated on the basis of historical data or market data and estimates of growth over a period of time can be arrived at. This estimated value will be used to determine incremental capacity requirements over time.

Application migration is the next parameter for consideration in right-sizing. What kind of applications do you plan to migrate to the Cloud?  What is the kind of processing power, throughput and latency do you need? What can you get from the Cloud? The final estimates will depend on the number of application instances that will have to be deployed, the processing power that will be required for the deployment of the specified application, the location of the users deploying the application, and the permissible latency. If historical data is available, the process of right-sizing may be easier. If not, test runs (such as load testing) may provide for some clarity on the issues associated with application deployment and right-sizing for them.

Service provider’s documentation will be a key to right-sizing. The documentation may give you an idea of the kind of server configurations that are being provided by the service provider. Any performance statistics available on the service will also be very useful in the exercise. The relationship between the server and the services will also be a determinant in the execution of the service level agreements. After all, you want to get what you have been promised!