Looking for a definitive Azure Sql Database sizing guide

Question

I am looking for an definitive Azure Sql Database sizing guide resource/helper for documenting a comparative sizing guide for moving to Azure Sql Database from hosted Sql Server.

This is our current guide for hosted Sql Server:

There seems to be a lot of "really helpful" sizing guides available for Sql Server that i have used before but am not able to find one where I can just input the current Sql Server sizing guide details and the tool outputs a comparative Azure Sql Server sizing guide.

Hosted Sql Server sizing guides used before:

SQL Server Sizing Resources

Hardware Sizing Microsoft SQL Server

Am I to assume that it is a 1-to-1 conversion for the sizing guide for Azure Sql DB from Sql Server??

Can someone please help me converting this above Sql Server sizing guide to one for Azure Sql DB or perhaps point me to a good resource??

Answer 1

It is a very good question. SQL server sizing guide is based on the CAL and performance. On the other hand, Azure-SQL has different tiers - Basic, Standard and Premium. Azure-SQL sizing is calculated based on database throughput units - DTUs. I am afraid, there may not be a direct sizing conversion available. Perhaps, you can refer to these two links,
Azure-SQL Tiers - https://learn.microsoft.com/en-us/azure/sql-database/sql-database-service-tiers DTU Calculator - http://dtucalculator.azurewebsites.net

Trust it helps.

Answer 2

In my opinion, the only way you can find out the right azure sql database tier that works for your application or scenario is keep trying different price tiers from lower to higher until you are satisfied. Those DTUs or eDTUs really are just for pricing purpose. Each tier has a Max database size. That probably is the only helpful information from those pricing tiers.

Depend on your application, there is a possibility that azure database might not work for your scenario, or even you can find a tier that works for you, but you can not afford it.

The DTU/eDTU does not tell you how many RAMs it uses. For sql server, the RAMs matters a lot.

There is a performance test here you can use as a reference. https://cbailiss.wordpress.com/azure-sql-db-performance-tests/ and https://cbailiss.wordpress.com/2015/01/31/azure-sql-database-v12-ga-performance-inc-cpu-benchmaring/ which includes a memory test.

If it works for you, then you can enjoy the good side of azure sql database. It means less maintenance work. Also, it is probably one of the most reliable services of azure so far.