Azure Web App runs very slowly

3
votes

We have an Azure web app for our production environment. The site is built with the Umbraco 7.2.6 CMS.

The web app Instance size is 'Large (4 Cores, 7GB memory)'

The database for this is a Standard SQL Azure S0 Level (10 DTUs).

When running this site on my local machine against the same SQL Azure database (exactly the same instance) the site is very fast.

However, on Azure the site runs painfully slowly. I cannot find any obvious reasons for this.

Does anybody have any suggestions for troubleshooting this issue?

3
azureumbracoazure-sql-database
Are you able to estimate how many transactions per second you are generating in your testing? Also, if you look at the performance graphs in the azure portal for your database, are any of the resources maxing out during the time you are testing? – JeremyWeir
Also, another sanity check: Is your website and your database located in two different geographic locations? – Tobiah Zarlez
After you identify where the issue is occurring, check out this other thread from Sep 2015 to see if it applies to your case. stackoverflow.com/questions/32397111/… There are a few responses with some upvotes that may help you. – Shahed C - MSFT
What does the Umbraco Log file say? Are there any exceptions? Are you using a single instance or have you enabled scaling on the WebApp? Maybe you could update your question with some of the things you've tried so far. – Robert Foster
Did you make some changes in the way you acces to the umbraco tables in the database? Do you use your own ORM instead? Because Umbraco API uses cache it might be something to check out. – Hernan Demczuk

3 Answers

1
votes

I had exactly the same issue: Azure Web App + Azure DB = Slow DB returns.

But on the other hand if I ran the app locally on my computer and connected to the azure DB, everything would be flash quick.

So I checked my app service and location. I was using S1 located in the US with DB in Australia.

  1. I upgraded to Premium S2
  2. Located my App and DB is same region. Now it is >10 times faster.

I would suggest checking these two first before looking into anything else.

0
votes

Change the database to S2, although it does not look taxed by the load of Umbraco it will make a big difference to performance.

Also the underlying storage of WebApps in Azure is quite slow and since Umbraco is local disc intensive then this is a factor if running a large site due to the Examine indexes.

There is a plugin replacing examine called "Azure Search for Umbraco" which will improve performance but may require a lot of rework dependant on site.

0
votes

I did not expect this problem, it seems unfortunate that the way to solve this problem is to upgrade. I think I will try to utilize the In App MySql database instead.