Azure SQL Database underperforming

Question

Has anyone else noticed a big decrease in Azure SQL database performance?

I run some pretty intensive procs on an S3 database, and queries that used to take approximately 2 hours are now taking double that to execute.

Previously the DTU usage used to sit at (or close to) 100% when executing the stored procs, but now sits at approx 50% for the same procs, so basically I am not getting full use of my 100 DTU database

Have things changed in Azure such that a single connection can no longer utilise the total capacity? 

Anyone experienced the same?

Answer 1

Hi P383,

Thanks for posting here.

What is the current database that you are using? is it V11 or V12.

If you are using V11, I suggest you to upgrade to V12 database where your DTU performance would be drastically high when compared with V11.

Ref: https://msdn.microsoft.com/library/azure/dn741327.aspx

https://azure.microsoft.com/en-us/documentation/articles/sql-database-v12-whats-new/

Please follow this article How to upgrade to V12 database

Hope this helps you.

In the mean while, I will involve the SQL experts for reviewing the SQL database performance with your current database.

Girish Prajwal

Answer 2

Hi Girish

Thanks for the reply.

I am already using V12. (Apologies for not stating this in my post)

Answer 3

Hi,

Performance from the back-end hasn't changed. I strongly recommend you to open a support ticket if you need guidance in improving performance. 

Said that, I would've started by looking at the index fragmentation level and comparing the query plans of bad queries with the good run (if available).

Also, try to restore the bacpac of a SQL Azure DB in a SQL Server 2012 or higher and run the DB across DTA (Database tuning adviser) to find the top indexes and statistics which can be helpful in improving the performance.

Ref:

1. Index fragmentation: http://blogs.msdn.com/b/dilkushp/archive/2013/07/28/fragmentation-in-sql-azure.aspx 

2. DTA:https://msdn.microsoft.com/en-IN/library/ms174202.aspx 

I hope that helps!

KKB

Answer 4

Thanks KKB.

My Azure subscription doesn't allow technical support, but I will try your suggestions and see how it goes.

Answer 5

Hi P383,

Should your problem persist, please send me an email to FIRSTNAME.LASTNAME @ Microsoft.com including your server and database name as well as the data since when you experiencing the issues and we will start an investigation on our end.

Thanks,

Jan