Q:

SignalR Performance with IIS 7.5

I've been using Signal R on a project for the last couple of weeks and its been performing great, I even did a stress test with Crank yesterday and got 1000 users with no real delay.
I need to move on to the next stage of testing today so I decided to move it to IIS 7.5
After moving it over and doing a quick touch test I decided to do another stress test - this time I only got to 10 users and the website was pretty much dead..
does anyone know why this would happen? I've followed all the information on the Signal R performance tuning and its made zero difference..
Can anyone help?

A:

In some cases the Maximum concurrent requests can be maxed out at ~10 (old default).  This was changed in later .net releases to default to 5000.  Judging on what's happening on your machine I'd assume that your default is still (somehow) ~10.
I know you said you looked over the SignalR performance tuning piece, but make sure your configurations are properly setup for the Maximum Concurrent Requests Per CPU section at https://github.com/SignalR/SignalR/wiki/Performance.  It makes sense to ignore the section thinking that 5k concurrent requests is enough, but in earlier releases the value was defaulted to be very low.
You can also check out: http://blogs.msdn.com/b/tmarq/archive/2007/07/21/asp-net-thread-usage-on-iis-7-0-and-6-0.aspx for more info regarding IIS concurrent request usages, particularly the 7th paragraph.

