Which model to choose between vCore and DTU during the installation of SQL database in Azure

Which model to choose between vCore and DTU during the installation of SQL database in Azure

Background:

vCore and DTU are the two different pricing models used for creating Azure SQL Database. User can choose any of these as per his/her requirement.

  • DTU (Database Transaction Unit) model was the first to be introduced with Azure SQL DB. DTU is a measure; a blend of CPU memory and IO.
  • vCore (virtual core) is a model that was designed to make it simpler to translate the on prem hardware resource specs into similar specs on the Azure SQL database platform. Here the user has the visibility into the actual amount of RAM that’s available to him along with the type and speed of the processor used.

Difference:
  • The underlying service is the same for both vCore and DTU model. It’s important to note that in both cases the service is priced per database.
  • In DTU model, user has to pay a fixed price for IO, memory, data storage and back up retention whereas in vCore model, user has more flexibility as it charges separately for separate components.
  • User doesn’t have to choose one or the other when getting started, he/she can switch between the DTU and vCore models.
  • To simplify, if the user is just getting started with Azure SQL Database, the DTU model offers more options at the lower end of performance, so you can get started at a lower price point than with vCore. However, If he / she  has software assurance with Microsoft and are familiar with how that works, there are some advantages there to using vCore.

Which one to choose from Orchestrator’s database perspective:
  • For Orchestrator’s database, vCore model is not needed. DTU model should be fine. Either one works for Orchestrator, but the most used is the DTU model. Here, the suggestion is DTU as this is the basic and cost-effective model.
  • 20 DTUs should be enough to server up to 50 robots.