Extremely uneven cloud service load-balancing with Azure

Question

I'm utilizing Azure for hosting a cloud service, which I recently modified to be scalable across multiple instances, including a session caching worker role. My question is, why would I be seeing extreme load (upwards of 90%) on one instance, but not on other instances (15-20% across all other instances)? Should I be worried?

Before I set up load balancing and when my single instance hit upwards of 95% load, it would slow to a crawl --- becoming unusable. Is there any way to ensure that I don't have any users experiencing this because they're somehow round-robin'd onto the overloaded instance?

Answer 1

We found we had a similar type of situation when one load-balanced instance failed over; what we were seeing is that all the load transferred, but wouldn't balance out again. We found that turning off keep-alive for a couple of minutes let the load spread again, after which we could turn it back on.

http://technet.microsoft.com/en-us/library/cc772183(v=ws.10).aspx