Provisioned Concurrency Causing Throttling

Bug Report

Description

1. What did you do?
   • Added 5 'containers' that are provisioned to my LIVE alias.
2. What happened?
   • Any additional requests over the 5 available containers was getting throttles
3. What should've happened?

• Additional requests over the 5 available containers should just spin up a new container as per before.

When i have no provisioned concurrency I never see even 1 throttle but when I add some which what I think of as 'pre-warmed' containers then any 'additional' requests are getting throttled which I didn't think was the point of this, I though they should only get throttled if I set the 'reserved concurrency' which I haven't that's current set to use the available which is around 2995.

Now i could just provision more containers to handle the max load but the reason is that the function normally has low traffic that 3-5 containers could handle but there are times throughout the day where extra would be required. For these times i'm happy for more containers to spin up with the cold start time adding some extra time.