Azure SQL wait operation timed out

Question

I'm about ready to abandon Azure SQL for reliability issues, but I thought I'd check here first. I'm getting several sporadic timeout errors on SQL Azure. This is not a connection string issue - we're talking about several different apps that have been running for quite some time without issue. The exact error is:

System.ComponentModel.Win32Exception: The wait operation timed out

At present time, I'm looking at 300 of these over the past 30 minutes or so. I ran the DMV query mentioned at http://blog.sqlauthority.com/2010/05/14/sql-server-find-most-expensive-queries-using-dmv to find out what's going on, and found this:

According to the documentation, 602,382 is microseconds, or roughly 602 milliseconds, so obviously my database usage requirements are pretty damn low. I have a feeling this is purely an over-tenancy issue on the part of Azure SQL. Is there any other possible explanation? Any potential resolution short of leaving Azure SQL for greener pastures (e.g. dedicated SQL VM)?

Answer 1

Yes, you're right, you're probably being stifled by other high-resource utilizing tenants that have been placed on the same machine your db was on.

By default, Sql Azure provides guarantees an SLA on availability but not performance. If you're looking for consistency in performance, you should look into their premium tier: http://www.windowsazure.com/en-us/pricing/details/sql-database/

In the premium tier, your db will be guaranteed say a couple of cores, memory and IOPS (think of it like a mini VM)

Answer 2

This error may occur due to a slow internet connection on the target machine.