Load testing on Azure

Hi,

I've been load testing a Sitefinity install on Azure using Blitz.io, but I'm killing the site in around 10 seconds with 1,000 users.

The setup I have is:

WebServer 1 - Medium - 2 instances
WebServer 2 - Medium - 2 instances
Load Balancer (Tried Failover & performance)

The CPU goes up to 95% on the instances within 10 seconds or so and doesn't come down until new instances are scaled, or I manually reboot them.

Any idea what would cause this and how I could go about fixing it?
Is this tool fine for load testing, or should I take a different method?

Thanks,

Gary

Hi,

Thank you for contacting the Telerik support.

Can you obtain and send us error logs from some of Azure instances?
In case you need more information how to do it, we have knowledge base article about this at:
http://www.sitefinity.com/developer-network/knowledge-base/how-to-get-the-error-log-from-sitefinity-deployment-to-azure

Having error logs may help us identify the reason for this behavior.

As long the question about load testing, I would recommend to provide some form of warm up of the instances before the actual test.
1. You may do it manually in case you know which URLs get hit by the test.
2. Or you may check with the tool options if there is warm up period. In case of Azure instances I believe that 10 minutes can be safe bet.
3. Also you can see if the tool provides another option - to not start with max number of users but start with 1 and gradually increase the number of users. And again - to start after the warm up.

Also bear in mind that running these test against your Azure account may incur increased fees for it. 

Regards,
GeorgePPetrov
Telerik