With lesser DTU we observe better performance on Azure SQL Server with Elastic Standard

Question

Context: During recent performance evaluation for our application we observed that with higher DTU's the response time were higher compare to lower DTU's.

Response Time Trend On the Application Front:

Resource Usage Pattern:

Not able to understand why with higher DTU's it perform Under and with lower DTU's it perform better. Any suggestions ?

Current Configuration: SQL Server Type: Elastic Standard SQL Elastic Pool Considered: 400, 300 & 100 DTU's

Note: Checked the Web App usage they are almost identical. We couldn't find any discrepancy there. Also check the SQL-Server Performance there are no indexing issue.

Answer 1

Higher service levels allow to higher degree of parallelism and lower service levels limit the the degree of parellism to 1. When you scale up to higher service tiers try limit the degree of parellism to 1.

ALTER DATABASE SCOPED CONFIGURATION SET MAXDOP = 1;